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%I #8 Mar 14 2014 14:04:10
%S 0,0,0,0,1,0,1,2,2,2,2,2,1,1,2,2,2,2,1,1,2,2,3,4,2,1,2,1,1,2,2,2,2,1,
%T 2,4,3,3,4,2,1,2,1,2,4,2,0,0,0,2,4,3,2,2,2,4,6,3,2,4,2,1,2,1,2,4,2,1,
%U 2,2,3,4,2,2,4,3,3,4,2,2,4,2,3,6,3,1,2,1,3,6,4,2,2,1,2,4,3,4,6,4,3,4,2,6,12
%N Number of different pairs of primes p,q such that : p<(q-2), p is a twin prime of p-2 or p+2 and q is a twin prime of q-2 or q+2, 2*n=p+q
%C conjecture : for n>2104 there is at least one such pair of primes p+q=2*n
%H Pierre CAMI, <a href="/A159700/b159700.txt">Table of n, a(n) for n=1..50000</a>
%e 3+13=16,5+11=16 so for n=8 2 pairs p,q such that p+q=2*8, p<(q-2) p and q have a twin prime
%o (Haskell)
%o a159700 n = length $ filter (\(p, q) -> p < q - 2 && a164292 q == 1) $
%o zip ps (map (2 * n -) ps)
%o where ps = filter ((== 1) . a164292) [1..n]
%o -- _Reinhard Zumkeller_, Mar 13 2014
%Y Cf. A164292.
%K nonn,look
%O 1,8
%A _Pierre CAMI_, Apr 20 2009