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 A020642 #10 Oct 09 2013 14:19:08 %S A020642 1,5,10,17,33,44,56,69,82,99,116,134,175,196,242,267,321,349,377,408, %T A020642 442,475,507,542,581,619,659,700,741,785,966,1015,1065,1111,1167,1273, %U A020642 1329,1383,1563,1622,1687,1751,1949,2017,2084,2159,2231,2302,2375,2449,2685 %N A020642 n-th composite is sum of first k composites for some k. %Y A020642 Cf. A013919, A013920, A013921. %K A020642 nonn %O A020642 1,2 %A A020642 _N. J. A. Sloane_, _Henri Lifchitz_, _David W. Wilson_