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%I #5 Mar 31 2012 13:22:06
%S 1,2,2,6,5,4,3,3,4,6,5,4,6,9,4,6,5,5,6,11,8,10,9,6,13,6,6,9,8,13,16,
%T 10,14,14,11,11,11,8,8,7,15,14,9,13,16,12,20,16,14,13,13,15,19,19,10,
%U 15,15,15,14,18,19,21,23,12,16,15,13,21,11,26,15,19,15,15,26,18,13,13,17,20
%N Number of pairs p,q with p < q such that 30*r(n)=p+q+2 and p p+2, q q+2 twin primes, r(i)=i-th prime.
%C The sequence is infinite: all numbers > 0 are present at least once and a(n) is always > 0.
%H Pierre CAMI, <a href="/A144160/b144160.txt">Table of n, a(n) for n = 1..10000</a>
%e 30*2=60 17+43=19+41=60 17,19 and 41,43 twin primes r(1)=2 so a(1)=1 30*3=90 17+73=19+71=90 17,19 as 71,73 twin primes 29+61=31+59=90 29,31 as 59,61 twin primes, r(2)=3 so a(2)=2
%K nonn
%O 1,2
%A _Pierre CAMI_, Sep 12 2008
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