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%I #7 Nov 19 2013 13:11:00
%S 10,21,55,110,253,1081,1265,1711,2530,3403,5671,11891,13861,15931,
%T 25651,34453,59455,60031,64261,73153,108811,114481,118910,126253,
%U 158203,171991,258121,351541,371953,392941,482653,518671,568301,703891,822403,853471,869221,933661
%N Squarefree numbers (from A005117) with prime divisors in a 2p+1 progression.
%C Squarefree numbers with k>=2 prime divisors of the form p_1 * p_2 * … * p_k, where p_1 < p_2 < … < p_k = primes with p_k = 2 * p_(k-1) + 1.
%C Supersequence of A156592 (numbers of the form p*q, p and q prime with q=2*p+1; see A005384 and A005385).
%e 118910 = 2*5*11*23*47, where 5 = 2*2 + 1, 11 = 2*5 + 1, 23 = 2*11 + 1, 47 = 2*23 + 1.
%Y Cf. A005117, A156592, A005384, A005385, A000040, A231967, A231968, A231969.
%K nonn
%O 1,1
%A _Jaroslav Krizek_, Nov 16 2013