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 A100648 #3 Mar 30 2012 16:50:06 %S A100648 8,45,144,105,17280,14175,5600,12474,1935360,1576575,28740096000, %T A100648 156370500,688816128,97692469875,26900729856000,158428270000, %U A100648 32593902501888000,3430178002251,1798063128576000,988320969417600,809280523999877529600000,461635966995328125 %N A100648 Denominator of Cotesian number C(n,3). %D A100648 Charles Jordan, Calculus of Finite Differences, Chelsea 1965, p. 513. %e A100648 1/8, 16/45, 25/144, 34/105, 2989/17280, 5248/14175, 1209/5600, 5675/12474, 560593/1935360, 893128/1576575, 11148172711/28740096000, 109420087/156370500, ... = A100627/A100628 %Y A100648 See A002176 for further references. A diagonal of A100640/A100641. %K A100648 nonn %O A100648 3,1 %A A100648 _N. J. A. Sloane_, Dec 05 2004