B-files added, and other things.

- A064572 Number of ways to partition n into parts which are all powers of some integer k
- A156681 Consider all Pythagorean triangles A^2 + B^2 = C^2 with A <B <C; sequence gives values of B, sorted to correspond to increasing A
- A257667 Primes containing a digit 5.
- A257668 Primes containing a digit 7.
- A020001 Nearest integer to GAMMA(n+11/12)/GAMMA(11/12).
- A020005 Nearest integer to GAMMA(n+10/11)/GAMMA(10/11).
- A064632 Smallest prime p such that n = (p-1)/(q-1) for some prime q.
- A018224 a(n) = C(n, floor(n/2))^2 = A001405(n)^2.
- A075584 Primes p such that the number of distinct prime divisors of all composite numbers between p and the next prime is 4.
- A075587 Primes p such that the number of distinct prime divisors of all composite numbers between p and the next prime is 7.
- A064632 Smallest prime p such that n = (p-1)/(q-1) for some prime q.
- A061076 a(n) is the sum of the products of the digits of all the numbers from 1 to n.
- A064652 Primes q associated with A064632.