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Numbers of prime triples (p,q,r), p<=q<=r, such that (p+q+r) divides n.
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%I #6 Mar 30 2012 18:39:12

%S 0,0,0,0,0,1,1,1,2,1,2,3,2,2,3,3,4,5,3,3,6,4,5,7,5,5,9,5,7,7,6,6,11,6,

%T 9,11,9,7,12,6,11,11,10,8,17,8,13,13,13,11,19,9,16,15,16,11,20,10,16,

%U 15,16,12,27,9,23,19,20,12,25,13,22,20,21,15,30,12,31,21,24,15,34,15,29,21

%N Numbers of prime triples (p,q,r), p<=q<=r, such that (p+q+r) divides n.

%o (PARI) a(n)=sum(i=1,n,sum(j=1,i,sum(k=1,j,if(n%(prime(i)+prime(j)+prime(k)),0,1))))

%K nonn

%O 1,9

%A _Benoit Cloitre_, Feb 02 2003