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%I #6 Mar 28 2015 22:38:49
%S 1,2,3,4,6,8,9,10,12,14,15,16,18,20,22,24,26,27,28,30,32,34,36,38,39,
%T 40,42,44,46,48,50,52,54,56,57,58,60,62,64,66,68,69,70,72,74,76,78,80,
%U 82,84,86,88,90,92,94,96,98,99,100,102,104,105,106,108,110
%N Numbers n such that one or more primes can be the arithmetic mean of 2 semiprimes whose difference is 2*n.
%C That is, there are several primes p, such that p+n and p-n are both semiprime.
%C Complement of A256387.
%C The terms of this sequence that do not belong to A256388 are even.
%e A256381 is the list of numbers n such that n-3 and n+3 are semiprimes, and it contains a single prime, hence 3 is in the sequence.
%e A256382 is the list of numbers n such that n-4 and n+4 are semiprimes, and it contains several primes, hence 4 is in the sequence.
%Y Cf. A124936, A105571, A256382.
%Y Cf. A256387 (no prime), A256388 (a single prime).
%K nonn
%O 1,2
%A _Michel Marcus_, Mar 27 2015
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