cp's OEIS Frontend

A087187 Number of ways to write n = i*p + j*q, where (p,q) is a twin prime pair and i,j>0.

%I A087187 #4 Feb 16 2025 08:32:51
%S A087187 0,0,0,0,0,0,0,1,0,0,1,1,1,1,0,1,2,1,2,1,1,2,2,3,1,3,2,2,3,1,3,3,3,3,
%T A087187 3,4,4,4,3,3,4,3,4,4,3,5,5,5,4,5,4,5,6,5,5,5,6,5,7,5,7,6,6,6,5,6,6,8,
%U A087187 6,7,7,8,7,9,6,8,7,7,8,7,8,8,9,8,8,8,10,8,12,8,10,10,9,10,8,10,9,10,9
%N A087187 Number of ways to write n = i*p + j*q, where (p,q) is a twin prime pair and i,j>0.
%C A087187 a(A054735(n)) > 0.
%H A087187 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/PrimePartition.html">Prime Partition</a>
%e A087187 n=50 = 5+5+5+5+5+5+5+3+3+3+3+3 = 5+5+5+5+3+3+3+3+3+3+3+3+3+3 =
%e A087187 5+3+3+3+3+3+3+3+3+3+3+3+3+3+3+3 = 7+7+7+7+7+5+5+5 = 13+13+13+11, therefore
%e A087187 a(50)=5
%Y A087187 Cf. A000607, A001359, A006512.
%K A087187 nonn
%O A087187 1,17
%A A087187 _Reinhard Zumkeller_, Aug 23 2003