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A128691 Numbers of the form 2^k*p, where 1 <= k <= 8 and p is a prime > 2. 3

%I

%S 6,10,12,14,20,22,24,26,28,34,38,40,44,46,48,52,56,58,62,68,74,76,80,

%T 82,86,88,92,94,96,104,106,112,116,118,122,124,134,136,142,146,148,

%U 152,158,160,164,166,172,176,178,184,188,192,194,202,206,208,212,214,218,224

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

%C 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.

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

%H Klaus Brockhaus, <a href="/A128691/b128691.txt">Table of n, a(n) for n=1..10000</a>

%e 40 = 2^3*5 is a term.

%o (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) ];

%Y Cf. A100368, A128645.

%K nonn

%O 1,1

%A _Klaus Brockhaus_, Mar 21 2007

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Last modified July 12 06:48 EDT 2020. Contains 335657 sequences. (Running on oeis4.)