A128691 Numbers of the form 2^k*p, where 1 <= k <= 8 and p is a prime > 2.

6, 10, 12, 14, 20, 22, 24, 26, 28, 34, 38, 40, 44, 46, 48, 52, 56, 58, 62, 68, 74, 76, 80, 82, 86, 88, 92, 94, 96, 104, 106, 112, 116, 118, 122, 124, 134, 136, 142, 146, 148, 152, 158, 160, 164, 166, 172, 176, 178, 184, 188, 192, 194, 202, 206, 208, 212, 214, 218, 224

Offset: 1

Author

Klaus Brockhaus, Mar 21 2007

Keywords

• nonn

Comments

Subsequence of A100368 (numbers of the form 2^k*p, where k>0 and p is an odd prime); 1536 = 2^9*3 is the smallest term of A100368 that is not in the present sequence.

Auxiliary sequence for A128645 which gives the number of groups of order a(n).

Examples

			40 = 2^3*5 is a term.
		

Links

• Klaus Brockhaus, Table of n, a(n) for n=1..10000

Crossrefs

Cf. A100368, A128645.

Programs

Magma

[ n: n in [1..225] | #t eq 2 and t[1, 1] eq 2 and t[1, 2] le 8 and t[2, 2] eq 1 where t is Factorization(n) ];