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OIES id | description | sound player | download | creator | quarter | tags | comments |
---|---|---|---|---|---|---|---|
A000040 | the primes | download | Penny Espinoza | Spr2017 | primes | ||
A000040 | the primes, starting from 107 | download | Penny Espinoza | Spr2017 | primes | ||
A000040 | the primes, starting from 108 | download | Penny Espinoza | Spr2017 | primes | ||
A000040 | the primes, starting from 109 | download | Penny Espinoza | Spr2017 | primes | ||
A000040 | the primes, starting from 1010 | download | Penny Espinoza | Spr2017 | primes | ||
A000040 | the primes, starting from 1011 | download | Penny Espinoza | Spr2017 | primes | ||
A000040 | the primes, starting from 1012 | download | Penny Espinoza | Spr2017 | primes | ||
A000040 | primes, starting at 1020 | download | Penny Espinoza | Spr2017 | primes | ||
A000040 | primes, starting at 1030 | download | Penny Espinoza | Spr2017 | primes | ||
A000040 | primes, starting at 1040 | download | Penny Espinoza | Spr2017 | primes | ||
A000040 | primes, starting at 10100 | download | Penny Espinoza | Spr2017 | primes | ||
A000040 | primes, starting at 10200 | download | Penny Espinoza | Spr2017 | primes | ||
A000040 | primes, starting at 10400 | download | Penny Espinoza | Spr2017 | primes | ||
A001097 | twin primes | download | Penny Espinoza | Win2017 | primes | ||
A077800 | twin primes, starting at 1010 (long sound file) | download | Penny Espinoza | Spr2017 | primes | ||
A077800 | twin primes, starting at 1030 (long sound file) | download | Penny Espinoza | Spr2017 | primes | ||
A077800 | twin primes, starting at 10100 (long sound file) | download | Penny Espinoza | Spr2017 | primes | ||
A005384 | Sophie Germain primes p: 2p+1 is also prime. | download | Miranda Bugarin | Spr2019 | primes | ||
A002858 | Ulam numbers | download | |||||
A005101 | Abundant numbers (sum of divisors of n exceeds 2n) | download | Nile Wymar | Aut2017 | |||
A005101 | Abundant numbers waveform built up from distinct subsequences. | download | Mrigank Arora | Spr2019 | |||
A091191 | Primitive abundant numbers: abundant numbers having no abundant proper divisor. | download | Mrigank Arora | Spr2019 | |||
A005100 | Deficient numbers: numbers n such that sigma(n) < 2n. | download | Nile Wymar | Aut2017 | comment | ||
A000217 | triangular numbers | download | Hannah Van Wyk | Aut2016 | polygonal,polynomial, quadratic | ||
A000290 | square numbers | download | Hannah Van Wyk | Aut2016 | polygonal,polynomial, quadratic | ||
A000326 | pentagonal numbers | download | Hannah Van Wyk | Aut2016 | polygonal,polynomial, quadratic | ||
A000384 | hexagonal numbers | download | Hannah Van Wyk | Aut2016 | polygonal,polynomial, quadratic | ||
A000566 | heptagonal numbers (or 7-gonal numbers): n(5n-3)/2 | download | Emily Flanagan | Win2017 | polynomial,quadratic | ||
A000567 | octagonal numbers | download | Hannah Van Wyk | Aut2016 | polygonal,polynomial, quadratic | ||
A000124 | quadratic sequence n(n+1)/2 + 1 | download | Emily Flanagan | Win2017 | polynomial,quadratic | ||
A005891 | centered pentagonal numbers: (5n^2+5n+2)/2 | download | Emily Flanagan, Jesse Rivera | Win2017 | polynomial,quadratic | ||
A005901 | quadratic sequence 10n^2 + 2 | download | Emily Flanagan | Win2017 | polynomial,quadratic | ||
A005905 | quadratic sequence 14n^2 + 2 | download | Emily Flanagan | Win2017 | polynomial,quadratic | ||
A005914 | quadratic sequence 12n^2 + 2 | download | Emily Flanagan | Win2017 | polynomial,quadratic | ||
A010003 | quadratic sequence 11n^2 + 2 | download | Emily Flanagan | Win2017 | polynomial,quadratic | ||
A010004 | quadratic sequence 13n^2 + 2 | download | Emily Flanagan | Win2017 | polynomial,quadratic | ||
A001504 | a(n) = (3n+1)(3n+2). | download | Joo Young "Jon" Kim | Spr2018 | polynomial, quadratic | ||
A000125 | Cake numbers: maximal number of pieces resulting from n planar cuts through a cube (or cake): C(n+1,3)+n+1, i.e., (n^3 + 5*n + 6) / 6 | download | Sherry Chen | Win2018 | polynomial | ||
A002144 | primes of the form 4m+1 | download | Jesse Rivera | Aut2016 | primes | ||
A002145 | primes of the form 4m+3 | download | Jesse Rivera | Aut2016 | primes | ||
A000959 | lucky numbers | download | Jesse Rivera | Aut2016 | |||
A045954 | even lucky numbers | download | Jesse Rivera | Aut2016 | |||
A003309 | Ludic numbers | download | Jesse Rivera | Aut2016 | |||
A040040 | averages of twin prime pairs, divided by 2 | download | Hannah Van Wyk | Aut2016 | primes | ||
A100317 | Numbers n such that exactly one of n-1 and n+1 is prime. | download | Aut2018 | ||||
A000062 | floor(n/(e-2)) | download | Jesse Rivera | Win2017 | beatty | ||
A001951 | floor(n sqrt(2)) | download | Jesse Rivera | Win2017 | beatty | ||
A022838 | floor(n sqrt(3)) | download | Jesse Rivera | Win2017 | beatty | ||
A022839 | floor(n sqrt(5)) | download | Jesse Rivera | Win2017 | beatty | ||
A022843 | floor(n e) | download | Jesse Rivera | Win2017 | beatty | ||
A022844 | floor(n pi) | download | Jesse Rivera | Win2017 | beatty | ||
A277723 | floor(n t^3), t = 1.839286755... | download | Hannah Van Wyk | Aut2016 | beatty | ||
A000201 | floor(n phi), phi=(1+sqrt(5))/2 | download | Jesse Rivera | Aut2016 | beatty | ||
A001950 | floor(n*phi^2) | download | Lisa Yan | Aut2017 | beatty | comment | |
A003622 | floor(n*phi^2) - 1, where phi = (1+sqrt(5))/2. | download | Pooja Ramathan | Aut2018 | beatty | comment | |
A108587 | floor(n/(1-sin(1))) | download | Hannah Van Wyk | Aut2016 | beatty | ||
A038152 | floor(n e^pi) | download | Jesse Rivera | Win2017 | beatty | ||
A038153 | floor(n pi^e) | download | Jesse Rivera | Win2017 | beatty | ||
A001952 | floor(n*(2 + sqrt(2))) | download | Emily Flanagan | Spr2017 | beatty | ||
A000572 | floor (n(e+1)) | download | Nile Wymar | Aut2017 | beatty | ||
A003152 | floor(n*(1+1/sqrt(2))) | download | Lisa Yan | Aut2017 | beatty | ||
A003511 | floor( n * (1 + sqrt(3))/2 ) | download | Lisa Yan | Aut2017 | beatty | ||
A059535 | floor( n * Pi^2/6 ) | download | Lisa Yan | Aut2017 | beatty | ||
A047381 | floor(n*7/5) | download | Lisa Yan | Aut2017 | beatty | ||
A003151 | floor(n*(1+sqrt(2))). | download | Robert Pedersen | Win2018 | beatty | ||
A080081 | floor(n*(3+sqrt(13))/2). | download | Robert Pedersen | Win2018 | beatty | ||
A110117 | floor(n*(sqrt(2) + sqrt(3))). | download | Robert Pedersen | Win2018 | beatty | ||
A050504 | floor of n log n | download | Hannah Van Wyk | Aut2016 | |||
A248360 | floor of 1/(1 - cos(Pi/n)) | download | Hannah Van Wyk | Aut2016 | |||
A001614 | Connell sequence: 1 odd, 2 even, 3 odd, ... | download | Jesse Rivera | Aut2016 | |||
A045928 | generalized Connell sequence C_{3,2} | download | Jesse Rivera | Aut2016 | |||
A122793 | Connell sum sequence (partial sums of the Connell sequence) | download | Jesse Rivera | Aut2016 | |||
A033293 | Connell-like sequence: take 1 number = 1 (mod Q), 2 numbers = 2 (mod Q), 3 numbers = 3 (mod Q), etc., where Q = 8 | download | Jesse Rivera | Aut2016 | |||
A033291 | Connell-like sequence: take the first multiple of 1, the next 2 multiples of 2, the next 3 multiples of 3, etc. | download | Jesse Rivera | Aut2016 | |||
A006046 | total number of odd numbers in the first n rows of Pascal's triangle | download | Jesse Rivera | Aut2016 | |||
A078177 | composite n with integer prime factor average | download | Jesse Rivera | Aut2016 | |||
A070003 | numbers divisible by the square of their largest prime factor | download | Hannah Van Wyk | Aut2016 | |||
A054010 | numbers divisible by the number of their proper divisors | download | Hannah Van Wyk | Aut2016 | |||
A033950 | numbers divisible by the number of their divisors | download | Hannah Van Wyk | Aut2016 | |||
A246294 | numbers n such that sin(n) < sin(n+1) > sin(n+2) | download | Hannah Van Wyk | Aut2016 | |||
A277096 | n such that sin(n)<0 and sin(n+2)<0 | download | Jesse Rivera | Aut2016 | |||
A004084 | tan n >0 and tan(n-1)<=0 | download | Jesse Rivera | Aut2016 | |||
A070752 | n such that sin(n) > 0 | download | |||||
A070753 | primes p such that sin(p) < 0 | download | Hannah Van Wyk | Aut2016 | primes | ||
A000059 | n such that (2n)^4+1 is prime | download | Xin Li | Aut2016 | |||
A256249 | partial sums of the sequence of solutions to the Josephus problem | download | Jesse Rivera | Aut2016 | |||
A003325 | sums of two positive cubes | download | Jesse Rivera | Aut2016 | |||
A024975 | sums of three positive cubes | download | Jesse Rivera | Aut2016 | |||
A004431 | sums of 2 distinct nonzero squares | download | Jesse Rivera | Aut2016 | |||
A002088 | sums of totient function: Sum_{k=1..n} phi(k) | download | Jesse Rivera | Aut2016 | |||
A078972 | brilliant numbers | download | Jesse Rivera | Aut2016 | |||
A006446 | numbers n such that floor(sqrt(n)) divides n | download | Emily Flanagan | Win2017 | |||
A023254 | numbers that remain prime through 2 iterations of the function f(x) = 5x + 6 | download | Emily Flanagan | Win2017 | primes | ||
A023255 | numbers that remain prime through 2 iterations of the function f(x) = 5x + 8 | download | Emily Flanagan | Win2017 | primes | ||
A023256 | numbers that remain prime through 2 iterations of the function f(x) = 6x + 1 | download | Emily Flanagan | Win2017 | primes | ||
A023257 | numbers that remain prime through 2 iterations of the function f(x) = 6x + 5 | download | Emily Flanagan | Win2017 | primes | ||
A023258 | numbers that remain prime through 2 iterations of the function f(x) = 6x + 7 | download | Emily Flanagan | Win2017 | primes | ||
A206399 | quadratic sequence 41n^2 + 2 | download | Emily Flanagan | Win2017 | |||
A259486 | 3n^2 - 3n + 1 + 6 floor((n-1)(n-2)/6) | download | Emily Flanagan | Win2017 | |||
A268037 | numbers n such that the number of divisors of n+2 divides n and the number of divisors of n divides n+2 | download | Emily Flanagan | Win2017 | |||
A002473 | numbers whose prime divisors are all <= 7 | download | Jesse Rivera | Win2017 | |||
A003136 | numbers of the form x^2 + xy + y^2 | download | Jesse Rivera | Win2017 | |||
A006218 | sum of the number of divisors of k, k=1,...,n | download | Jesse Rivera | Win2017 | |||
A011257 | geometric mean of phi(n) and sigma(n) is an integer | download | Jesse Rivera | Win2017 | |||
A030513 | numbers with four divisors | download | Jesse Rivera | Win2017 | |||
A030626 | numbers with eight divisors | download | Jesse Rivera | Win2017 | |||
A036844 | numbers divisible by the sum of their prime factors | download | Jesse Rivera | Win2017 | |||
A100118 | Sum of prime factors with multiplicity is prime. | download | Aut2018 | ||||
A051038 | 11-smooth numbers: numbers whose primes divisors are all <= 11 | download | Jesse Rivera | Win2017 | |||
A051913 | numbers n such that phi(n)/phi(phi(n)) = 3 | download | Jesse Rivera | Win2017 | |||
A080683 | numbers whose prime divisors are all <= 23 | download | Jesse Rivera | Win2017 | |||
A165350 | primes p such that floor((p^2-1)/4)+p is not prime | download | Jesse Rivera | Win2017 | primes | ||
A190751 | n+[ns/r]+[nt/r]+[nu/r]+[nv/r]+[nw/r], where r=sinh(x), s=cosh(x), t=tanh(x), u=csch(x), v=sech(x), w=coth(x), where x=pi/2 | download | Jesse Rivera | Win2017 | |||
A252895 | numbers with an odd number of square divisors | download | Jesse Rivera | Win2017 | |||
A274685 | odd numbers n such that sigma(n) is divisible by 5 | download | Jesse Rivera | Win2017 | |||
A277052 | n+floor(n/(2/sqrt(Pi)-1)) | download | Jesse Rivera | Win2017 | |||
A250046 | numbers n such that m = floor(n/7) is coprime to n and, if nonzero, m is also a term of the sequence | download | Penny Espinoza | Win2017 | |||
A250046 | numbers n such that m = floor(n/7) is coprime to n and, if nonzero, m is also a term of the sequence (longer version) | download | Penny Espinoza | Win2017 | |||
A250048 | numbers n such that m = floor(n/6) is coprime to n and, if nonzero, m is also a term of the sequence | download | Penny Espinoza | Win2017 | |||
A250050 | numbers n such that m = floor(n/5) is coprime to n and, if nonzero, m is also a term of the sequence | download | Penny Espinoza | Win2017 | |||
A250036 | numbers n such that m = floor(n/4) is coprime to n and, if nonzero, m is also a term of the sequence | download | Penny Espinoza | Win2017 | |||
A250038 | numbers n such that m = floor(n/16) is coprime to n and, if nonzero, m is also a term of the sequence | download | Penny Espinoza | Win2017 | |||
A250040 | numbers n such that m = floor(n/10) is coprime to n and, if nonzero, m is also a term of the sequence | download | Penny Espinoza | Win2017 | |||
A250042 | numbers n such that m = floor(n/9) is coprime to n and, if nonzero, m is also a term of the sequence | download | Penny Espinoza | Win2017 | |||
A250044 | numbers n such that m = floor(n/8) is coprime to n and, if nonzero, m is also a term of the sequence | download | Penny Espinoza | Win2017 | |||
A161165 | the n-th twin prime plus the n-th isolated prime | download | Penny Espinoza | Win2017 | primes | ||
A166251 | isolated primes: primes p such that there is no other prime in the interval [2 prevprime(p/2), 2 nextprime(p/2)] | download | Penny Espinoza | Win2017 | primes | ||
A167706 | single or isolated numbers: the union of single (or isolated or non-twin) primes and single (or isolated or average of twin prime pairs) nonprimes | download | Penny Espinoza | Win2017 | primes | ||
A167771 | Twice-isolated primes: primes p such that neither p+-2 nor p+-4 is prime | download | Penny Espinoza | Win2017 | primes | ||
A065049 | Odd primes of incorrect parity: number of 1's in the binary representation of n (mod 2) equals 1 - (n mod 3) (mod 2). Also called isolated primes. | download | Penny Espinoza | Win2017 | primes | ||
A147778 | positive integers of the form u*v*(u^2-v^2) where u,v are co-prime integers | download | Penny Espinoza | Win2017 | |||
A153777 | minimal sequence S such that 1 is in S and if x is in S, then 5x-1 and 5x+1 are in S | download | Penny Espinoza | Win2017 | |||
A153777 | minimal sequence S such that 1 is in S and if x is in S, then 5x-1 and 5x+1 are in S (10 minute version: silence after 4:36) | download | Penny Espinoza | Win2017 | |||
A003586 | 3-smooth numbers: numbers of the form 2^i 3^j with i, j >= 0 | download | Penny Espinoza | Win2017 | |||
A033845 | numbers of the form 2^i 3^j, with i,j >= 1 | download | Penny Espinoza | Win2017 | |||
A052160 | isolated prime difference equals 6: d(n)=p(n+1)-p(n)=6 but d(n+1) and d(n-1) differ from 6 | download | Penny Espinoza | Win2017 | primes | ||
A007510 | single, isolated or non-twin primes: primes p such that neither p-2 nor p+2 is prime | download | Penny Espinoza | Win2017 | primes | ||
A181732 | numbers n such that 90n + 1 is prime | download | Penny Espinoza | Win2017 | |||
A196000 | numbers n such that 90n + 19 is prime | download | Penny Espinoza | Win2017 | |||
A198382 | numbers n such that 90n + 37 is prime | download | Penny Espinoza | Win2017 | |||
A201734 | numbers n such that 90n + 47 is prime | download | Penny Espinoza | Win2017 | |||
A195993 | numbers n such that 90n + 73 is prime | download | Penny Espinoza | Win2017 | |||
A196007 | numbers n such that 90n + 83 is prime | download | Penny Espinoza | Win2017 | |||
A006450 | prime-indexed primes: primes with prime subscripts | download | Penny Espinoza | Win2017 | primes | ||
A066643 | floor(pi n^2) | download | Penny Espinoza | Win2017 | |||
A184774 | primes of the form floor(k*sqrt(2)) | download | Emily Flanagan | Spr2017 | primes | ||
A184775 | numbers n such that floor(n*sqrt(2)) is prime | download | Emily Flanagan | Spr2017 | |||
A184777 | primes of the form 2k + floor(k*sqrt(2)) | download | Emily Flanagan | Spr2017 | primes | ||
A184778 | numbers n such that 2n+floor(n*sqrt(2)) is prime | download | Emily Flanagan | Spr2017 | |||
A002984 | a(0) = 1; for n>0, a(n) = a(n-1) + floor( sqrt a(n-1) ) | download | Emily Flanagan | Spr2017 | |||
A013929 | non-squarefree numbers | download | Emily Flanagan | Spr2017 | |||
A017533 | number of the form 12n+1 | download | Emily Flanagan | Spr2017 | |||
A158708 | primes p such that p + floor(p/2) is prime | download | Emily Flanagan | Spr2017 | primes | ||
A158709 | primes p such that p + ceiling(p/2) is prime | download | Emily Flanagan | Spr2017 | primes | ||
A168363 | squares and cubes of primes | download | Emily Flanagan | Spr2017 | primes | ||
A175914 | primes p such that p+2*q is prime, where q is the prime after p | download | Emily Flanagan | Spr2017 | primes | ||
A000093 | a(n) = floor(n^(3/2)). | download | Emily Flanagan | Spr2017 | |||
A000212 | a(n) = floor((n^2)/3) | download | Emily Flanagan | Spr2017 | |||
A002620 | quarter-squares: floor(n/2)*ceiling(n/2), equivalently, floor(n^2/4) | download | Emily Flanagan | Spr2017 | |||
A003154 | centered 12-gonal numbers (also star numbers: 6*n*(n-1) + 1). | download | Emily Flanagan | Spr2017 | |||
A007590 | floor(n^2/2) | download | Emily Flanagan | Spr2017 | |||
A014657 | numbers n that divide 2^k + 1 for some k | download | Emily Flanagan | Spr2017 | |||
A032528 | concentric hexagonal numbers: floor( 3*n^2 / 2 ) | download | Emily Flanagan | Spr2017 | |||
A033581 | a(n) = 6*n^2 | download | Emily Flanagan | Spr2017 | |||
A035336 | a(n) = 2*floor(n*phi) + n - 1, where phi = (1+sqrt(5))/2 | download | Emily Flanagan | Spr2017 | |||
A072065 | numbers of the form 12n+k, where k=0, 2, 9, or 11 | download | Penny Espinoza | Spr2017 | |||
A000068 | Numbers n such that n^4 + 1 is prime. | download | Nile Wymar | Aut2017 | |||
A000879 | Number of primes < prime(n)^2 | download | Nile Wymar | Aut2017 | |||
A001043 | Numbers that are the sum of 2 successive primes | download | Nile Wymar | Aut2017 | |||
A000277 | 3*n - 2*floor(sqrt(4*n+5)) + 5 | download | Nile Wymar | Aut2017 | |||
A007066 | a(n) = 1 + ceiling((n-1)*phi^2), phi = (1+sqrt(5))/2. | download | Nile Wymar | Aut2017 | |||
A007645 | Generalized cuban primes: primes of the form x^2 + xy + y^2; or primes of the form x^2 + 3*y^2; or primes == 0 or 1 mod 3. | download | Nile Wymar | Aut2017 | primes | ||
A027699 | Evil primes: primes with even number of 1's in their binary expansion. | download | Jingyun Du | Aut2019 | |||
A125494 | Composite evil numbers. | download | Jingyun Du | Aut2019 | |||
A000069 | odious numbers: numbers with an odd number of 1's in their binary expansion | download | Emily Flanagan | Win2017 | |||
A000057 | Primes dividing all Fibonacci sequences. | download | Sherry Chen | Win2018 | primes | ||
A000099 | Let A(n) = #{(i,j): i^2 + j^2 <= n}, V(n) = Pi*n, P(n) = A(n) - V(n); sequence gives values of n where |P(n)| sets a new record. | download | Sherry Chen | Win2018 | |||
A000123 | Number of binary partitions: number of partitions of 2n into powers of 2. | download | Sherry Chen | Win2018 | |||
A034048 | Numbers with multiplicative digital root = 0. | download | Sherry Chen | Win2018 | |||
A277061 | Numbers with multiplicative digital root > 0. | download | Sherry Chen | Win2018 | |||
A000977 | Numbers that are divisible by at least three different primes. | download | Robert Pedersen | Win2018 | |||
A002971 | Numbers k such that 4*k^2 + 25 is prime. | download | Robert Pedersen | Win2018 | |||
A003153 | a(n) = integer nearest n*(1+sqrt(2)). | download | Robert Pedersen | Win2018 | |||
A005574 | Numbers k such that k^2 + 1 is prime. | download | Robert Pedersen | Win2018 | |||
A007064 | Numbers not of form "nearest integer to n*tau", tau=(1+sqrt(5))/2. | download | Robert Pedersen | Win2018 | |||
A001913 | Full reptend primes: primes with primitive root 10. | download | Joo Young "Jon" Kim | Spr2018 | primes | ||
A023204 | Numbers m such that m and 2*m + 3 are both prime. | download | Joshua Ramirez | Spr2018 | primes | ||
A039770 | Numbers n such that phi(n) is a perfect square. | download | Joshua Ramirez | Spr2018 | |||
A006532 | Numbers n such that sum of divisors of n is a square. | download | Joshua Ramirez | Spr2018 | |||
A276967 | Odd integers n such that 2^n == 2^3 (mod n). | download | Joshua Ramirez | Spr2018 | |||
A003624 | Duffinian numbers: n composite and relatively prime to sigma(n). | download | Joshua Ramirez | Spr2018 | |||
A015765 | Numbers n such that phi(n) | sigma_7(n). | download | Joshua Ramirez | Spr2018 | |||
A005835 | Pseudoperfect (or semiperfect) numbers n: some subset of the proper divisors of n sums to n. | download | Joshua Ramirez | Spr2018 | |||
A007675 | Numbers n such that n, n+1 and n+2 are squarefree. | download | Joshua Ramirez | Spr2018 | |||
A001122 | Primes with primitive root 2. | download | Joshua Ramirez | Spr2018 | primes | ||
A152088 | Positive integers n that when written in binary have exactly the same number of (non-leading) 0's as the number of divisors of n. | download | Joshua Ramirez | Spr2018 | |||
A023172 | Self-Fibonacci numbers: numbers n such that n divides Fibonacci(n). | download | Joshua Ramirez | Spr2018 | |||
A001837 | Numbers n such that phi(2n+1) < phi(2n). | download | Joshua Ramirez | Spr2018 | |||
A001105 | a(n) = 2*n^2. | download | Erik Huang | Aut2018 | quadratic,polynomial | ||
A001964 | Wythoff game. | download | Erik Huang | Aut2018 | |||
A002061 | Central polygonal numbers: a(n) = n^2 - n + 1. | download | Erik Huang | Aut2018 | |||
A002113 | Palindromes in base 10. | download | Erik Huang | Aut2018 | |||
A002808 | The composite numbers: numbers n of the form x*y for x > 1 and y > 1. | download | Erik Huang | Aut2018 | |||
A006995 | Binary palindromes: numbers whose binary expansion is palindromic. | download | Erik Huang | Aut2018 | |||
A007623 | Integers written in factorial base. | download | Erik Huang | Aut2018 | |||
A018252 | The nonprime numbers (1 together with the composite numbers). | download | Erik Huang | Aut2018 | |||
A029803 | Numbers that are palindromic in base 8. | download | Erik Huang | Aut2018 | |||
A029952 | Palindromic in base 5. | download | Erik Huang | Aut2018 | |||
A029953 | Palindromic in base 6. | download | Erik Huang | Aut2018 | |||
A029954 | Palindromic in base 7. | download | Erik Huang | Aut2018 | |||
A029955 | Palindromic in base 9. | download | Erik Huang | Aut2018 | |||
A139250 | Toothpick sequence. | download | Erik Huang | Aut2018 | |||
A001358 | Semiprimes | download | Pooja Ramathan | Aut2018 | |||
A100484 | Even semiprimes | download | Pooja Ramathan | Aut2018 | |||
A107961 | products of two primes which are not congruent to 3 modulo 4 | download | Aut2019 | ||||
A000469 | 1 together with products of 2 or more distinct primes | download | Nile Wymar | Aut2017 | |||
A007304 | Sphenic numbers: products of 3 distinct primes. | download | Robert Pedersen | Win2018 | |||
A030059 | Numbers that are the product of an odd number of distinct primes | download | Nile Wymar | Aut2017 | |||
A005728 | Number of fractions in Farey series of order n. | download | Pooja Ramathan | Aut2018 | |||
A005994 | Alkane (or paraffin) numbers l(7,n). | download | Pooja Ramathan | Aut2018 | |||
A112393 | Semiprimes n such that 3*n - 2 is a square. | download | Pooja Ramathan | Aut2018 | |||
A277093 | Numbers k such that sin(k) > 0 and sin(k+2) > 0. | download | Pooja Ramathan | Aut2018 | |||
Approximation of A277093 based on difference pattern [6,6,6,7,6,6,6,1] | download | Pooja Ramathan | Aut2018 | ||||
Approximation of A277093 based on difference pattern [6,6,6,7,6,6,6,1,6,6,6,7,6,6,6,1,6, 6,6,7,6,6,6,1,6,6,6,7,6,6,6,1,6,6, 6,7,6,6,6,1,6,6,6,7,6,6,6,1,6,6,6, 7,6,6,6,1,6,6,6,7] | download | Pooja Ramathan | Aut2018 | ||||
A277094 | Numbers k such that sin(k) > 0 and sin(k+2) < 0. | download | Pooja Ramathan | Aut2018 | |||
A277095 | Numbers k such that sin(k) < 0 and sin(k+2) > 0. | download | Pooja Ramathan | Aut2018 | |||
A192869 | Thin primes: odd primes p such that p+1 is a prime (or 1) times a power of two. | download | Mrigank Arora | Spr2019 | primes | ||
A003234 | Numbers n such that A003231(A001950(n)) = A001950(A003231(n)) - 1. | download | Miranda Bugarin | Spr2019 | |||
A007640 | Numbers k such that 2*k^2 - 2*k + 19 is composite. | download | Miranda Bugarin | Spr2019 | |||
A155107 | Numbers n that are 23 or 30 (mod 53). | download | Miranda Bugarin | Spr2019 | |||
A000404 | Numbers that are the sum of 2 nonzero squares. | download | Aanya Khaira | Spr2019 | |||
A000443 | Numbers that are the sum of 2 squares in exactly 3 ways. | download | Aanya Khaira | Spr2019 | |||
A025284 | Numbers that are the sum of 2 nonzero squares in exactly 1 way. | download | Aanya Khaira | Spr2019 | |||
A025285 | Numbers that are the sum of 2 nonzero squares in exactly 2 ways. | download | Aanya Khaira | Spr2019 | |||
A025286 | Numbers that are the sum of 2 nonzero squares in exactly 3 ways. | download | Aanya Khaira | Spr2019 | |||
A025287 | Numbers that are the sum of 2 nonzero squares in exactly 4 ways. | download | Aanya Khaira | Spr2019 | |||
A000408 | Numbers that are the sum of three nonzero squares. | download | Aanya Khaira | Spr2019 | |||
Numbers that are the sum of 3 nonzero squares in exactly n ways where n is increasing geometrically by doubling every 2.2 seconds. | download | Aanya Khaira | Spr2019 | ||||
A025324 | Numbers that are the sum of 3 nonzero squares in exactly 4 ways | download | Aanya Khaira | Spr2019 | |||
A025325 | Numbers that are the sum of 3 nonzero squares in exactly 5 ways | download | Aanya Khaira | Spr2019 | |||
A025326 | Numbers that are the sum of 3 nonzero squares in exactly 6 ways | download | Aanya Khaira | Spr2019 | |||
A025327 | Numbers that are the sum of 3 nonzero squares in exactly 7 ways | download | Aanya Khaira | Spr2019 | |||
A025328 | Numbers that are the sum of 3 nonzero squares in exactly 8 ways | download | Aanya Khaira | Spr2019 | |||
A025329 | Numbers that are the sum of 3 nonzero squares in exactly 9 ways | download | Aanya Khaira | Spr2019 | |||
A025330 | Numbers that are the sum of 3 nonzero squares in exactly 10 ways | download | Aanya Khaira | Spr2019 | |||
A008846 | Hypotenuses of primitive Pythagorean triangles | download | Jin Lin | Aut2019 | |||
A225771 | Numbers that are positive integer divisors of 1 + 2*x^2 where x is a positive integer | download | Jin Lin | Aut2019 | |||
A000379 | Numbers n where total number of 1-bits in the exponents of their prime factorization is even; a 2-way classification of integers: | download | Jin Lin | Aut2019 | |||
A000328 | Number of points of norm <= n^2 in square lattice. | download | Jin Lin | Aut2019 | |||
A164620 | Primes p such that 1 +p*floor(p/2) is also prime. | download | Pubo Huang | Aut2019 | primes | ||
A164624 | Primes p such that p+floor(p/2)+floor(p/3) is prime. | download | Pubo Huang | Aut2019 | primes | comment | |
A164625 | Primes p such that p+floor(p/2)+floor(p/3)+floor(p/5) is prime. | download | Pubo Huang | Aut2019 | primes | ||
A000960 | Flavius Josephus's sieve numbers. | download | Pubo Huang | Aut2019 | |||
A046959 | Numbers n where sin(n) increases monotonically to 1. | download | Pubo Huang | Aut2019 | |||
A259368 | Number of binary digits of n^n. | download | Pubo Huang | Aut2019 | |||
floor( n atan(n/10^3)) | download | Pubo Huang | Aut2019 | ||||
floor( n atan(n/10^4)) | download | Pubo Huang | Aut2019 | ||||
floor( n atan(n/10^5)) | download | Pubo Huang | Aut2019 | strictly increasing portion of floor( n atan(n/10^6)) | download | Aut2019 | |
A000430 | Primes and squares of primes. | download | Sam Wang | Aut2019 | |||
A000452 | The greedy sequence of integers which avoids 3-term geometric progressions. | download | Sam Wang | Aut2019 | |||
A000549 | Numbers that are the sum of 2 squares but not sum of 3 nonzero squares. | download | Sam Wang | Aut2019 | |||
A000966 | n! never ends in this many 0's. | download | Sam Wang | Aut2019 | |||
A001101 | Moran numbers: n such that (n / sum of digits of n) is prime. | download | Sam Wang | Aut2019 | |||
A001123 | Primes with 3 as smallest primitive root. | download | Sam Wang | Aut2019 | |||
A007624 | Product of proper divisors of n = n^k, k>1. | download | Sam Wang | Aut2019 | |||
A007634 | Numbers n such that n^2 + n + 41 is composite. | download | Sam Wang | Aut2019 | |||
A007638 | Numbers k such that 3*k^2 - 3*k + 23 is composite. | download | Sam Wang | Aut2019 | |||
A007692 | Numbers that are the sum of 2 nonzero squares in 2 or more ways. | download | Sam Wang | Aut2019 | |||
A007774 | Numbers that are divisible by exactly 2 different primes. | download | Sam Wang | Aut2019 | |||
A003277 | Cyclic numbers: n such that n and phi(n) are relatively prime; | download | Sam Wang | Aut2019 | |||
A003159 | Numbers n whose binary representation ends in an even number of zeros. | download | Sam Wang | Aut2019 | |||
A002035 | Numbers that contain primes to odd powers only. | download | Sam Wang | Aut2019 | primes | ||
A001958 | floor( (n+1/3) * (5+sqrt(13)) /2) | download | Sam Wang | Aut2019 | |||
A001958 approximation: difference sequence is 5, 4, 4, 4, 5, 4, 4, 5, 4, 4, then repeats. | download | Sam Wang | Aut2019 | ||||
A014574 | Average of twin prime pairs. | download | Jingyun Du | Aut2019 | |||
A045718 | Nearest neighbors of primes. | download | Jingyun Du | Aut2019 | |||
A088485 | Numbers n such that n^2 + n - 1 and n^2 + n + 1 are twin primes. | download | Jingyun Du | Aut2019 | |||
A111980 | Union of pairs of consecutive primes p, q with q-p = 4. | download | Jingyun Du | Aut2019 | |||
A000037 | Numbers that are not squares (or, the nonsquares). | download | Ally Krinsky | Win2020 | |||
A002328 | Numbers n such that n^2-n-1 is prime. | download | Ally Krinsky | Win2020 | |||
A002642 | Numbers n such that (n^2+n+1)/3 is prime. | download | Ally Krinsky | Win2020 | |||
A002643 | Numbers n such that (n^2+n+1)/19 is prime. | download | Ally Krinsky | Win2020 | |||
A002644 | Numbers n such that (n^2+n+1)/21 is prime. | download | Ally Krinsky | Win2020 | |||
A002731 | Numbers n such that (n^2+1)/2 is prime. | download | Ally Krinsky | Win2020 | |||
A002733 | Numbers n such that (n^2 + 1)/10 is prime. | download | Ally Krinsky | Win2020 | |||
A002970 | Numbers n such that 4*n^2 + 9 is prime. | download | Ally Krinsky | Win2020 | |||
A004083 | Numbers n such that cos(n-1) <= 0 and cos(n) > 0. | download | Ally Krinsky | Win2020 | |||
A002640 | Numbers n such that (n^2 + n + 1)/3 is prime. | download | Ally Krinsky | Win2020 | |||
A002641 | Numbers n such that (n^2 + n + 1)/7 is prime. | download | Ally Krinsky | Win2020 | |||
A002642 | Numbers n such that (n^2 + n + 1)/7 is prime. | download | Ally Krinsky | Win2020 | |||
A002643 | Numbers n such that (n^2 + n + 1)/7 is prime. | download | Ally Krinsky | Win2020 | |||
A004614 | Numbers that are divisible only by primes congruent to 3 mod 4. | download | Ally Krinsky | Win2020 | |||
A007519 | Primes congruent to 1 mod 8. | download | Ally Krinsky | Win2020 | primes | ||
A007520 | Primes congruent to 3 mod 8. | download | Ally Krinsky | Win2020 | primes | ||
A007521 | Primes congruent to 5 mod 8. | download | Ally Krinsky | Win2020 | primes | ||
A001000 | a(n) = least m such that if a/b < c/d where a,b,c,d are integers in [0,n], then a/b < k/m < c/d for some integer k. | download | Thien Do | Win2020 | |||
A001748 | 3*primes. | download | Thien Do | Win2020 | |||
A001750 | 5*primes. | download | Thien Do | Win2020 | |||
A001915 | Primes p such that the congruence 2^x = 3 (mod p) is solvable. | download | Thien Do | Win2020 | primes | ||
A002970 | Numbers n such that 4*n^2 + 9 is prime. | download | Thien Do | Win2020 | |||
A100317 | Numbers k such that exactly one of k - 1 and k + 1 is prime. | download | Thien Do | Win2020 | |||
A004759 | Binary expansion starts 111. | download | Thien Do | Win2020 | |||
A006532 | Numbers n such that sum of divisors of n is a square. | download | Thien Do | Win2020 | |||
A014580 | Binary irreducible polynomials (primes in the ring GF(2)[X]), evaluated at X=2. | download | Thien Do | Win2020 | |||
A015782 | Phi(n) + 3 divides sigma(n + 3). | download | Thien Do | Win2020 | |||
A024917 | a(n) = Sum_{k=2..n} k*floor(n/k). | download | Thien Do | Win2020 | |||
A006995 | palindromes in base 2 | download | Jesse Rivera | Aut2016 | digits | ||
A014190 | palindromes in base 3 | download | Jesse Rivera | Aut2016 | digits | ||
A014192 | palindromes in base 4 | download | Jesse Rivera | Aut2016 | digits | ||
A077436 | sums of binary digits of n and n^2 are equal | download | Hannah Van Wyk | Aut2016 | digits | ||
A006753 | Smith numbers: composite numbers n such that sum of digits of n = sum of digits of prime factors of n (counted with multiplicity). | download | Erik Huang | Aut2018 | digits | comment | |
A104390 | 2-Smith numbers. | download | Erik Huang | Aut2018 | digits | ||
A050224 | 1/2-Smith numbers. | download | Erik Huang | Aut2018 | digits | ||
A028834 | sum of digits is a prime | download | Hannah Van Wyk | Aut2016 | digits | ||
A028839 | sum of digits is a square | download | Hannah Van Wyk | Aut2016 | digits | ||
A054683 | Sum of digits is even | download | Nile Wymar | Aut2017 | digits | ||
A268620 | sum of digits is a multiple of 4 | download | Hannah Van Wyk | Aut2016 | digits | ||
A005349 | numbers divisible by their digit sum | download | Jesse Rivera | Aut2016 | digits | ||
A057531 | Numbers n such that sum of digits of n equals the numbers of divisors of n. | download | Joshua Ramirez | Spr2018 | digits | ||
A028838 | Sum of digits of n is a power of 2 | download | Nile Wymar | Aut2017 | digits | ||
A028840 | Sum of digits of n is a Fibonacci number | download | Nile Wymar | Aut2017 | digits | ||
A295389 | Sum of digits is square-free | download | Nile Wymar | Aut2017 | digits | ||
A018900 | Sum of digits in base 2 is 2 | download | Penny Espinoza | Win2017 | digits | ||
A226636 | Sum of digits in base 3 is 3 | download | Penny Espinoza | Win2017 | digits | ||
A226969 | Sum of digits in base 4 is 4 | download | Penny Espinoza | Win2017 | digits | ||
A227062 | Sum of digits in base 5 is 5 | download | Penny Espinoza | Win2017 | digits | ||
A227080 | Sum of digits in base 6 is 6 | download | Penny Espinoza | Win2017 | digits | ||
A227092 | Sum of digits in base 7 is 7 | download | Penny Espinoza | Win2017 | digits | ||
A227095 | Sum of digits in base 8 is 8 | download | Penny Espinoza | Win2017 | digits | ||
A227238 | Sum of digits in base 9 is 9 | download | Penny Espinoza | Win2017 | digits | ||
A052224 | Sum of digits in base 10 is 10 | download | Penny Espinoza | Win2017 | digits | ||
A052223 | Sum of digits is 9. | download | Erik Huang | Aut2018 | digits | ||
A235151 | Sum of digits is 12. | download | Erik Huang | Aut2018 | digits | ||
A235227 | Sum of digits is 16 | download | Nile Wymar | Aut2017 | digits | ||
A166459 | Sum of digits is 19. | download | Erik Huang | Aut2018 | digits | ||
A235229 | Sum of digits is 20. | download | Erik Huang | Aut2018 | digits | ||
Sum of digits is 25. | download | Nile Wymar | Aut2017 | digits | |||
Sum of digits is 36. | download | Nile Wymar | Aut2017 | digits | |||
A061910 | Numbers n sum of digits of n^2 is a square | download | Nile Wymar | Aut2017 | digits | ||
Base 2 version of A61910: n such that sum of binary digits of n^2 is square | download | Nile Wymar | Aut2017 | digits | |||
A237525 | Numbers n such that the sum of digits of n^3 is a cube | download | Nile Wymar | Aut2017 | digits | ||
A084561 | Sum of binary digits is a square | download | Nile Wymar | Aut2017 | digits | ||
A001969 | Sum of binary digits is even (Evil numbers) | download | Nile Wymar | Aut2017 | digits | ||
n such that the sum of digits of n^3 is one more than a cube | download | Nile Wymar | Win2018 | digits | |||
n such that the digit sum of n^4 is a fourth power | download | Nile Wymar | Win2018 | digits | |||
n such that the digit sum of n^2 is 28 | download | Pubo Huang | Aut2019 | digits | |||
n such that the digit sum of n^2 is 31 | download | Pubo Huang | Aut2019 | digits | |||
n such that the digit sum of n^2 is 54 | download | Nile Wymar | Win2018 | digits | |||
n such that the digit sum of n^2 is 54 (extra long version: to 107) | download | Sum2021 | digits | ||||
n such that the digit sum of n^2 is 72 | download | Pubo Huang | Aut2019 | digits | |||
n such that sum of digits of n^3 equals 80 | download | Nile Wymar | Win2018 | digits | |||
n such that sum of digits of n^4 equals 99 | download | Nile Wymar | Win2018 | digits | |||
A004207 | a(0) = 1, a(n) = sum of digits of all previous terms | download | Nile Wymar | Win2018 | digits | ||
A004207 | A004207 beginning at 6666706 | download | Nile Wymar | Win2018 | digits | ||
A004207 | A004207 beginning at 10000000042 | download | Nile Wymar | Win2018 | digits | ||
A254621 | Zerofree numbers having product of digits less than or equal to sum of digits | download | Sherry Chen | Win2018 | digits | ||
A062996 | Sum of digits is greater than or equal to product of digits. | download | Sherry Chen | Win2018 | digits | ||
A007091 | numbers in base 5 | download | Jesse Rivera | Aut2016 | digits | ||
numbers which contain their digital root among their digits more than once | download | Jesse Rivera | Aut2016 | digits | |||
A031443 | base 2 digitally balanced numbers | download | Hannah Van Wyk | Aut2016 | digits | ||
A072600 | numbers which in base 2 have fewer zeros than ones among their digits | download | Hannah Van Wyk | Aut2016 | digits | ||
A093083 | Partial sums of digits of decimal expansion of golden ratio, phi. | download | Pubo Huang | Aut2019 | digits | ||
Partial sums of digits of randomly-generated decimal expansion. | download | Pubo Huang | Aut2019 | digits | |||
A000788 | Total number of 1's in binary expansions of 0, ..., n. | download | Jin Lin | Aut2019 | digits | ||
A054632 | Partial sums of the sequence of digits of the natural numbers: 1,2,3,..,9,1,0,1,1,1,2,1,3,1,4,... | download | Jin Lin | Aut2019 | digits | ||
A067112 | Partial sums of the sequence of digits of the primes (2,3,5,7,1,1,1,3,...) | download | Jin Lin | Aut2019 | digits | ||
A067113 | Partial sums of the sequence of digits of the squares (1,4,9,1,6,2,5,...) | download | Jin Lin | Aut2019 | digits | ||
Partial sums of the sequence of digits of n^3 | download | Jin Lin | Aut2019 | digits | |||
Partial sums of the sequence of digits of n^4 | download | Jin Lin | Aut2019 | digits | |||
Partial sums of the sequence of digits of n^5 | download | Jin Lin | Aut2019 | digits | |||
Partial sums of the sequence of digits of n^n | download | Jin Lin | Aut2019 | digits | |||
A039918 | Partial sums of the decimal digits of pi | download | Jesse Rivera | Aut2016 | digits | ||
A099534 | Partial sums of the digits in decimal expansion of e | download | Jin Lin | Aut2019 | digits | ||
A099539 | Partial sums of the digits in decimal expansion of sqrt(2) | download | Jin Lin | Aut2019 | digits | ||
Partial sums of digits in decimal expansion of 2^sqrt(2) | download | Jin Lin | Aut2019 | digits | |||
Partial sums of the digits in decimal expansion of sqrt(3) | download | Jin Lin | Aut2019 | digits | |||
A055471 | Divisible by the product of its nonzero digits. | download | Miranda Bugarin | Spr2019 | digits | ||
A071204 | Numbers which are multiples of their largest decimal digit. | download | Miranda Bugarin | Spr2019 | digits | ||
A052382 | Numbers without 0 as a base 10 digit, a.k.a. zeroless numbers. | download | Miranda Bugarin | Spr2019 | digits | ||
A082943 | Numbers without zero digits that are not divisible by any of their digits nor by the sum of their digits. | download | Miranda Bugarin | Spr2019 | digits | ||
A031956 | Numbers in which the number of distinct base 4 digits is 3. | download | Miranda Bugarin | Spr2019 | digits | ||
A031957 | Numbers in which the number of distinct base 5 digits is 3. | download | Miranda Bugarin | Spr2019 | digits | ||
A031958 | Numbers in which the number of distinct base 6 digits is 3. | download | Miranda Bugarin | Spr2019 | digits | ||
A031959 | Numbers in which the number of distinct base 7 digits is 3. | download | Miranda Bugarin | Spr2019 | digits | ||
A031960 | Numbers in which the number of distinct base 8 digits is 3. | download | Miranda Bugarin | Spr2019 | digits | ||
A031961 | Numbers in which the number of distinct base 9 digits is 3. | download | Miranda Bugarin | Spr2019 | digits | ||
A031962 | Numbers with exactly two distinct base 10 digits. | download | Miranda Bugarin | Spr2019 | digits | ||
A031955 | Numbers with exactly two distinct base 10 digits. | download | Miranda Bugarin | Spr2019 | digits | ||
A101594 | Numbers with exactly two distinct decimal digits, neither of which is 0. | download | Miranda Bugarin | Spr2019 | digits | ||
A002796 | Numbers that are divisible by each nonzero digit. | download | digits | ||||
A028374 | Curved numbers: numbers that only have curved digits (0,2,3,5,6,8,9) | download | Mrigank Arora | Spr2019 | digits | ||
A034470 | Prime numbers using only the curved digits (0,2,3,5,6,8,9) | download | Mrigank Arora | Spr2019 | digits | ||
A242756 | Semiprimes having only the curved digits. | download | Pooja Ramathan | Aut2018 | digits | ||
A028846 | Numbers n such that the product of the digits of n is a power of 2. | download | Aut2019 | digits | |||
A276038 | Numbers n such that the product of the digits of n is a power of 6. | download | Aut2019 | digits | |||
A227510 | Numbers such that product of digits of n is positive and a substring of n. | download | Sherry Chen | Win2018 | digits | ||
A236402 | Numbers with property that the sum of any pair of adjacent digits is a substring of the number. | download | Sherry Chen | Win2018 | digits | ||
A236402 | Numbers with property that the sum of any pair of adjacent digits is a substring of the number (sequence starting from 21!) | download | Sherry Chen | Spr2018 | digits | ||
A014261 | Numbers that contain odd digits only. | download | Sherry Chen | Spr2018 | digits | ||
A059708 | Numbers n such that all digits have same parity. | download | Sherry Chen | Spr2018 | digits | ||
A267085 | Numbers such that the number formed by digits in even position divides, or is divisible by, the number formed by the digits in odd position; both must be nonzero. | download | Sherry Chen | Spr2018 | digits | ||
A267086 | Numbers such that the number formed by digits in even positions divides, or is divisible by, the number formed by the digits in odd positions; zero allowed. (terms up to 5x106) | download | Sherry Chen | Spr2018 | digits | ||
A267086 | Numbers such that the number formed by digits in even positions divides, or is divisible by, the number formed by the digits in odd positions; zero allowed. (terms between 1010 and 1010+5x106 ) | download | Sherry Chen | Spr2018 | digits | ||
A007602 | Numbers that are divisible by the product of their digits. | download | Joshua Ramirez | Spr2018 | digits | ||
A110806 | Numbers n such that sum of the digits as well as number of digits divides n. | download | Joshua Ramirez | Spr2018 | digits | ||
A036301 | Numbers n such that sum of even digits of n equals sum of odd digits of n. | download | digits | comment | |||
A007770 | Happy numbers: numbers whose trajectory under iteration of sum of squares of digits map includes 1. | download | Erik Huang | Aut2018 | digits | comment | |
A010784 | Numbers with distinct decimal digits. | download | Erik Huang | Aut2018 | digits | ||
A014486 | List of totally balanced sequences of 2n binary digits written in base 10. Binary expansion of each term contains n 0's and n 1's and reading from left to right (the most significant to the least significant bit), the number of 0's never exceeds the number of 1's. | download | Erik Huang | Aut2018 | digits | ||
A072543 | Numbers whose largest decimal digit is also the initial digit (to 107) | download | Erik Huang | Aut2018 | digits | ||
A153880 | Shift factorial base representation left by one digit (to 4 million) | download | Erik Huang | Aut2018 | digits | ||
A243615 | Numbers n whose digital sum equals the number of binary digits in its binary expansion. | download | Erik Huang | Aut2018 | digits | ||
A243617 | Numbers n whose sum of digits equals the number of bits in its binary expansion. No zeros allowed in the digital expansion. | download | Erik Huang | Aut2018 | digits | ||
A004678 | Primes written in base 4. | download | Pooja Ramathan | Aut2018 | digits | ||
A004680 | Primes written in base 6. | download | Pooja Ramathan | Aut2018 | digits | ||
A004754 | Numbers whose binary expansion starts 10. | download | Pooja Ramathan | Aut2018 | digits | ||
A004758 | Binary expansion starts 110. | download | Pooja Ramathan | Aut2018 | digits | ||
A100290 | Numbers divisible by smallest number with same number of 1's in its binary expansion. | download | Aut2019 | digits | |||
A054518 | Emirpnons (nonprimes whose reversal is a different nonprime). | download | Aut2019 | digits | |||
A056177 | Sum of a(n) terms of 1/k^(1/5) first exceeds n. | download | Aut2019 | ||||
A072192 | Index of primes p for which 2p+1 is prime. | download | Aut2019 | ||||
A075025 | n for which d(n)<d(n-1) and d(n)<d(n+1) | download | Aut2019 | ||||
A192109 | Numbers n such that n divides 2^(n-1) - 2. | download | Aut2019 | ||||
A291625 | Numbers n such that n^2 has a zero digit. | download | Win2020 | ||||
A291625 | Numbers n such that n^2 has a zero digit (extra long verstion: to 107) | download | Sum2021 |