# Sound Library

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OIES id description sound player download creator quarter tags comments
A000040 the primes download Penny Espinoza Spr2017 primes
A001097 twin primes download Penny Espinoza Win2017 primes
A005384 Sophie Germain primes p: 2p+1 is also prime. download Miranda Bugarin Spr2019 primes
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
A277723 floor of n t^3, t = 1.839286755... download Hannah Van Wyk Aut2016 beatty
A000201 floor of n phi, phi=(1+sqrt(5))/2 download Jesse Rivera Aut2016 beatty
A108587 floor of n/(1-sin(1)) download Hannah Van Wyk Aut2016 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 primes
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
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
A006995 palindromes in base 2 download Jesse Rivera Aut2016
A014190 palindromes in base 3 download Jesse Rivera Aut2016
A014192 palindromes in base 4 download Jesse Rivera Aut2016
A077436 sums of binary digits of n and n^2 are equal download Hannah Van Wyk Aut2016 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
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
A039918 partial sums of the digits of pi download Jesse Rivera Aut2016 digits
A007091 numbers in base 5 download Jesse Rivera Aut2016
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
A072600 numbers which in base 2 have fewer zeros than ones among their digits download Hannah Van Wyk Aut2016 digits
A000069 odious numbers: numbers with an odd number of 1's in their binary expansion download Emily Flanagan Win2017
A000566 heptagonal numbers (or 7-gonal numbers): n(5n-3)/2 download Emily Flanagan Win2017 polynomial,quadratic
A005891 centered pentagonal numbers: (5n^2+5n+2)/2 download Emily Flanagan, Jesse Rivera Win2017 polynomial,quadratic
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
A000062 floor(n/(e-2)) download Jesse Rivera Win2017 beatty
A001951 floor(n sqrt(2)) download Jesse Rivera Win2017 beatty
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
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
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
A038152 floor(n e^pi) download Jesse Rivera Win2017 beatty
A038153 floor(n pi^e) download Jesse Rivera Win2017 beatty
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
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
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
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
A001952 a Beatty sequence: a(n) = floor(n*(2 + sqrt(2))) download Emily Flanagan Spr2017 beatty
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
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
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 1010 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
A077800 twin primes, starting at 1010 download Penny Espinoza Spr2017 primes
A077800 twin primes, starting at 1030 download Penny Espinoza Spr2017 primes
A077800 twin primes, starting at 10100 download Penny Espinoza Spr2017 primes
A000059 Numbers n such that (2n)^4 + 1 is prime. download Nile Wymar Aut2017
A000068 Numbers n such that n^4 + 1 is prime. download Nile Wymar Aut2017
A000469 1 together with products of 2 or more distinct primes 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
A000062 a(n) = floor(n/(e-2)). download Nile Wymar Aut2017 beatty
A000572 a(n)= floor (n(e+1)) download Nile Wymar Aut2017 beatty
A000277 3*n - 2*floor(sqrt(4*n+5)) + 5 download Nile Wymar Aut2017
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
A007066 a(n) = 1 + ceiling((n-1)*phi^2), phi = (1+sqrt(5))/2. download Nile Wymar Aut2017
A007510 Single (or isolated or non-twin) primes: Primes p such that neither p-2 nor p+2 is prime download Nile Wymar Aut2017 primes
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
A030059 Numbers that are the product of an odd number of distinct primes download Nile Wymar Aut2017
A047381 floor(n*7/5) download Lisa Yan Aut2017 beatty
A001950 floor(n*phi^2) download Lisa Yan 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
A028834 Numbers n such that the sum of digits of n is a prime. download Nile Wymar Aut2017 digits
A028838 Numbers n such that the sum of digits of n is a power of 2 download Nile Wymar Aut2017 digits
A028839 Number n such that the sum of digits of n is a square download Nile Wymar Aut2017 digits
A028840 Numbers n such that the sum of digits of n is a Fibonacci number download Nile Wymar Aut2017 digits
A054683 Numbers n such that the sum of digits is even download Nile Wymar Aut2017 digits
A295389 Numbers n such that the sum of digits is square-free download Nile Wymar Aut2017 digits
A061910 Numbers n such that the 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
A235227 Numbers n such that the sum of digits is 16 download Nile Wymar Aut2017 digits
Numbers n such that sum of digits is 25 download Nile Wymar Aut2017 digits
Numbers n such that sum of digits is 36 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 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 sum of digits of n^4 is a fourth power download Nile Wymar Win2018 digits
n such that sum of digits of n^2 equals 54 download Nile Wymar Win2018 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
A004207 A004207 beginning at 10000000042 download Nile Wymar Win2018
A000057 Primes dividing all Fibonacci sequences. download Sherry Chen Win2018 primes
A000059 Numbers n such that (2n)^4 + 1 is prime. download Sherry Chen Win2018
A000062 A Beatty sequence: a(n) = floor(n/(e-2)). download Sherry Chen Win2018 beatty
A000068 Numbers n such that n^4 + 1 is prime. download Sherry Chen Win2018
A000069 Odious numbers: numbers with an odd number of 1's in their binary expansion. download Sherry Chen Win2018
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
A000124 Central polygonal numbers (the Lazy Caterer's sequence): n(n+1)/2 + 1; or, maximal number of pieces formed when slicing a pancake with n cuts. download Sherry Chen Win2018 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. download Sherry Chen Win2018 polynomial,quadratic
A034048 Numbers with multiplicative digital root = 0. download Sherry Chen Win2018
A277061 Numbers with multiplicative digital root > 0. download Sherry Chen Win2018
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
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
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
A003151 Beatty sequence for 1+sqrt(2); a(n) = floor(n*(1+sqrt(2))). download Robert Pedersen Win2018 beatty
A003152 A Beatty sequence: a(n) = floor(n*(1+1/sqrt(2))). download Robert Pedersen Win2018 beatty
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
A022843 Beatty sequence for e: a(n) = floor(n*e). download Robert Pedersen Win2018 beatty
A080081 Beatty sequence for (3+sqrt(13))/2. download Robert Pedersen Win2018 beatty
A007304 Sphenic numbers: products of 3 distinct primes. download Robert Pedersen Win2018
A007064 Numbers not of form "nearest integer to n*tau", tau=(1+sqrt(5))/2. download Robert Pedersen Win2018
A110117 Beatty sequence for sqrt(2) + sqrt(3). download Robert Pedersen Win2018 beatty
A001913 Full reptend primes: primes with primitive root 10. download Joo Young "Jon" Kim Spr2018 primes
A001504 a(n) = (3n+1)(3n+2). download Joo Young "Jon" Kim Spr2018
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
A236402 Numbers with property that the sum of any pair of adjacent digits is a substring of the number. download Sherry Chen Spr2018 digits
A236402-21fact 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
A007304 Sphenic numbers: products of 3 distinct primes. download Joshua Ramirez Spr2018
A023204 Numbers m such that m and 2*m + 3 are both prime. download Joshua Ramirez Spr2018 primes
A007602 Numbers that are divisible by the product of their digits. download Joshua Ramirez Spr2018 digits
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
A057531 Numbers n such that sum of digits of n equals the numbers of divisors of n. download Joshua Ramirez Spr2018 digits
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
A110806 Numbers n such that sum of the digits as well as number of digits divides n. download Joshua Ramirez Spr2018 digits
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
A036301 Numbers n such that sum of even digits of n equals sum of odd digits of n. download digits comment
A000069 Odious numbers: numbers with an odd number of 1's in their binary expansion. download Erik Huang Aut2018
A000959 Lucky numbers download Erik Huang Aut2018
A001105 a(n) = 2*n^2. download Erik Huang Aut2018
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
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
A006995 Binary palindromes: numbers whose binary expansion is palindromic. download Erik Huang Aut2018
A007602 Numbers that are divisible by the product of their digits. download Erik Huang Aut2018 digits
A007623 Integers written in factorial base. download Erik Huang Aut2018
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
A014190 Palindromes in base 3 (written in base 10). download Erik Huang Aut2018
A014192 Palindromes in base 4 (written in base 10). download Erik Huang Aut2018
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
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
A050224 1/2-Smith numbers. download Erik Huang Aut2018
A052223 Numbers whose sum of digits is 9. download Erik Huang Aut2018 digits
A072543 Numbers whose largest decimal digit is also the initial digit (to 107) download Erik Huang Aut2018 digits
A104390 2-Smith numbers. download Erik Huang Aut2018
A139250 Toothpick sequence. download Erik Huang Aut2018
A153880 Shift factorial base representation left by one digit (to 4 million) download Erik Huang Aut2018 digits
A166459 Numbers whose sum of digits is 19. download Erik Huang Aut2018 digits
A235151 Numbers whose sum of digits is 12. download Erik Huang Aut2018 digits
A235229 Numbers whose sum of digits is 20. 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
A003622 The Wythoff compound sequence AA: [n*phi^2] - 1, where phi = (1+sqrt(5))/2. download Pooja Ramathan Aut2018 beatty
A004678 Primes written in base 4. download Pooja Ramathan Aut2018
A004680 Primes written in base 6. download Pooja Ramathan Aut2018
A004754 Numbers whose binary expansion starts 10. download Pooja Ramathan Aut2018
A004758 Binary expansion starts 110. download Pooja Ramathan Aut2018
A005728 Number of fractions in Farey series of order n. download Pooja Ramathan Aut2018
A005891 Centered pentagonal numbers: (5n^2+5n+2)/2. download Pooja Ramathan Aut2018
A005994 Alkane (or paraffin) numbers l(7,n). download Pooja Ramathan Aut2018
A100484 Even semiprimes download Pooja Ramathan Aut2018
A112393 Semiprimes n such that 3*n - 2 is a square. download Pooja Ramathan Aut2018
A242756 Semiprimes having only the curved digits. download Pooja Ramathan Aut2018 digits
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
A277096 Numbers k such that sin(k) < 0 and sin(k+2) < 0. download Pooja Ramathan Aut2018
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
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
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
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
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
A000408 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