A031127 Number of proper factorizations of p1^n*p2^4, where p1 and p2 are distinct primes.

4, 11, 28, 56, 108, 188, 322, 521, 830, 1278, 1940, 2875, 4214, 6065, 8643, 12150, 16932, 23335, 31920, 43263, 58249, 77824, 103361, 136370, 178974, 233531, 303267, 391830, 504068, 645519, 823418, 1046066, 1324135, 1669949, 2099103

Offset

0,1

Links

Ray Chandler, Table of n, a(n) for n = 0..100

Formula

a(n) = A000465(n) - 1 = A028422(2^n*3^4). - Ray Chandler, May 01 2017

Crossrefs

Cf. A000465, A028422.

Sequence in context: A096124 A269076 A282641 * A239031 A289217 A329141

Adjacent sequences: A031124 A031125 A031126 * A031128 A031129 A031130

Keyword

nonn

Author

Jeff Burch

Extensions

Offset changed to 0 and more terms added by Ray Chandler, May 01 2017

Status

approved