This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A242802 #5 May 23 2014 09:42:24
%S A242802 0,0,0,1,2,2,2,2,4,2,2,2,4,3,4,3,3,3,3,5,4,3,5,5,3,4,2,3,3,4,2,3,4,5,
%T A242802 3,4,2,3,3,5,3,5,4,7,3,3,5,7,4,7,6,4,5,9,5,5,5,5,6,9,4,5,8,6,8,6,4,6,
%U A242802 8,5,10,7,6,8,9,5,14,10,6,7
%N A242802 Number of primes p < n such that n - p is a term of A242754.
%C A242802 Conjecture: a(n) > 0 for all n > 3.
%H A242802 Zhi-Wei Sun, <a href="/A242802/b242802.txt">Table of n, a(n) for n = 1..10000</a>
%e A242802 a(4) = 1 since 2 is prime with 4 - 2 = 2 a term of A242754.
%t A242802 p[n_]:=PrimeQ[PowerMod[n,-1,Prime[n]]]
%t A242802 a[n_]:=Sum[Boole[p[n-Prime[k]]],{k,1,PrimePi[n-1]}]
%t A242802 Table[a[n],{n,1,80}]
%Y A242802 Cf. A000040, A242753, A242754, A242755.
%K A242802 nonn
%O A242802 1,5
%A A242802 _Zhi-Wei Sun_, May 23 2014