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 A003637 M2263 #9 Jan 27 2014 08:57:35 %S A003637 1,1,1,1,1,3,3,1,2,1,5,1,2,3,1,7,5,3,3,1,4,5,3,4,1,5,1,5,5,3,5,7,2,5, %T A003637 1,11,5,4,1,13,1,9,2,3,7,2,7,5,3,1,15,3,7,3,2,13,1,11,3,7,2,4,4,5,3, %U A003637 19,5,2,6,3,9,3,5,2,19,9,4,3,17,7,4,4,1,8,3,5,9,1,21,1,15,5,7,3,5,7,7,8,25 %N A003637 Number of classes per genus in quadratic field with discriminant -4n+1. %D A003637 D. A. Buell, Binary Quadratic Forms. Springer-Verlag, NY, 1989, pp. 224-241. %D A003637 N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence). %Y A003637 Cf. A003638. %K A003637 nonn %O A003637 1,6 %A A003637 _N. J. A. Sloane_, _Mira Bernstein_