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 A216278 #10 Jun 24 2017 12:13:11
%S A216278 0,0,1,0,0,1,0,0,1,0,1,1,0,0,0,0,1,1,1,0,0,1,0,1,0,0,2,0,0,0,0,0,2,1,
%T A216278 0,1,0,1,0,0,1,0,1,1,0,0,0,1,0,0,2,0,0,2,0,0,2,0,1,0,0,0,0,0,0,2,1,1,
%U A216278 0,0,0,1,1,0,1,1,0,0,0,0,2,1,1,0,0,1,0,1,1,0,0,0,0,0,0,1,1,0,3,0,0,2,0,0,0,0,1,2,0,0,0,0,1,2,0,0,0,1,0,0
%N A216278 Number of solutions to the equation x^2+2y^2 = n with x and y > 0.
%t A216278 r[n_] := Reduce[x > 0 && y > 0 && x^2 + 2 y^2 == n, Integers];
%t A216278 a[n_] := Which[rn = r[n]; rn === False, 0, Head[rn] === And, 1, Head[rn] === Or, Length[rn], True, -1];
%t A216278 Table[a[n], {n, 1, 120}] (* _Jean-François Alcover_, Jun 24 2017 *)
%Y A216278 Cf. A092573, A119395, A000161, A025426.
%K A216278 nonn
%O A216278 1,27
%A A216278 _V. Raman_, Sep 03 2012