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 A216279 #8 Jun 06 2016 23:21:29 %S A216279 0,0,0,0,0,1,0,0,1,0,0,0,0,1,0,0,0,0,0,0,2,0,0,1,0,0,0,0,1,1,0,0,0,0, %T A216279 0,1,0,0,0,0,1,0,0,0,1,1,0,0,1,0,0,0,0,2,0,1,0,0,0,0,1,0,0,0,0,0,0,0, %U A216279 2,1,0,0,0,0,0,0,0,0,0,0,2,0,0,2,0,1,0,0,1,0,0,0,0,1,0,1,0,0,0,0,1,0,0,0,2,0,0,0,1,0,0,0,0,0,0,1,0,0,0,1 %N A216279 Number of solutions to the equation x^2+5y^2 = n with x and y > 0. %H A216279 Charles R Greathouse IV, <a href="/A216279/b216279.txt">Table of n, a(n) for n = 1..10000</a> %o A216279 (PARI) a(n)=sum(k=1,sqrtint((n-1)\5), issquare(n-5*k^2)) \\ _Charles R Greathouse IV_, Jun 06 2016 %o A216279 (PARI) list(lim)=my(v=vector(lim\1),t); for(y=1,sqrtint((#v-1)\5), t=5*y^2; for(x=1,sqrtint(#v-t), v[x^2+t]++)); v \\ _Charles R Greathouse IV_, Jun 06 2016 %Y A216279 Cf. A092573, A119395, A000161, A025426. %K A216279 nonn %O A216279 1,21 %A A216279 _V. Raman_, Sep 03 2012