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 A128691 Numbers of the form 2^k*p, where 1 <= k <= 8 and p is a prime > 2. 3
 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 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 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). LINKS Klaus Brockhaus, Table of n, a(n) for n=1..10000 EXAMPLE 40 = 2^3*5 is a term. PROG (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) ]; CROSSREFS Cf. A100368, A128645. Sequence in context: A088829 A036348 A100368 * A028919 A325231 A134620 Adjacent sequences:  A128688 A128689 A128690 * A128692 A128693 A128694 KEYWORD nonn AUTHOR Klaus Brockhaus, Mar 21 2007 STATUS approved

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Last modified December 3 13:43 EST 2021. Contains 349463 sequences. (Running on oeis4.)