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%I #3 Mar 30 2012 18:50:26
%S 0,0,0,0,0,1,1,1,2,0,2,1,3,1,1,1,3,1,4,0,2,1,4,1,4,1,2,1,5,0,6,1,2,1,
%T 4,1,7,1,2,0,7,1,8,1,1,1,8,1,7,0,2,1,9,1,7,1,3,1,9,0,10,1,3,1,6,1,10,
%U 1,4,0,11,1,11,1,3,1,10,1,12,0,4,1,12,1,9,1,4,1,13,0,10,1,4,1,10,1,14,1,4
%N Number of pairs (p,q) of successive primes with p+q<=n and gcd(p+q,n)=1.
%C a(n) = A076471(n) - A076472(n).
%e n=27: gcd(2+3,27)=1, gcd(3+5,27)=1, gcd(5+7,27)=3, gcd(7+11,27)=9, gcd(11+13,27)=3, hence a(27)=2.
%Y Cf. A000010.
%K nonn
%O 1,9
%A _Reinhard Zumkeller_, Oct 14 2002
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