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%I #7 Mar 30 2012 18:40:59
%S 7,11,15,17,19,23,27,29,31,35,39,41,43,47,49,51,55,59,63,65,67,69,71,
%T 75,77,79,83,87,91,95,97,99,101,103,109,111,113,115,119,123,127,129,
%U 131,135,137,139,143,147,151,153,155,159,163,167,169,171,173,175
%N Odd n > 1 such that n+1 is a semiprime times a power of two.
%C Odd n (A005408(i>0; 2*j+1 for j>0) such that n+1 is a semiprime times a power of two. Odd n such that n+1 is a A001358(i) times a power of two. Odd n such that n+1 is in A192991. This is to thin numbers A192868 as semiprimes A001358 are to primes A000040.
%F a(n) = A192991(n) - 1.
%e 239 is in the sequence because 239+1 = 240 = 6th semiprime * 2^4 = 3 * 5 * 16.
%Y Cf. A005408, A001358, A192868, A192990, A192991.
%K nonn,easy
%O 1,1
%A _Jonathan Vos Post_, Jul 13 2011
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