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A159704 Number of different pairs of primes p,q such that : p<q, p is a cousin prime of p-4 or p+4 and q is a cousin prime of q-4 or q+4, 2*n=p+q 3

%I

%S 0,0,0,0,0,0,0,0,0,1,0,2,1,1,2,1,1,2,0,1,0,1,0,2,2,1,4,2,2,4,1,2,2,0,

%T 1,0,1,0,2,2,1,4,2,2,4,1,2,2,1,1,2,2,1,4,3,2,6,4,3,8,3,4,6,1,3,2,2,1,

%U 4,3,2,6,4,3,8,1,4,2,0,1,0,2,0,4,3,2,6,3,3,6,2,3,4,1,2,2,1,1,2,3,1,6,4,3,8

%N Number of different pairs of primes p,q such that : p<q, p is a cousin prime of p-4 or p+4 and q is a cousin prime of q-4 or q+4, 2*n=p+q

%C conjecture : for n>5573 there is at least one such pair of primes p+q=2*n

%H Pierre CAMI, <a href="/A159704/b159704.txt">Table of n, a(n) for n=1..50000</a>

%e 11+13=24,7+17=24 so for n=12 2 pairs p,q such that p+q=2*12, p<q p and q have a cousin prime

%K nonn

%O 1,12

%A _Pierre CAMI_, Apr 20 2009

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Last modified June 22 21:29 EDT 2021. Contains 345393 sequences. (Running on oeis4.)