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 A124567 #3 Mar 30 2012 18:37:01 %S A124567 1,1,3,22,317,7581,272914,13975298,981599065,92344174075, %T A124567 11474433841581,1869937363283342,398202456366104555, %U A124567 110561615797436467938,39978343388337757968279,18814183279605303823720601 %N A124567 Main diagonal of table A124560. %Y A124567 Cf. A124560; A124557 (variant). %K A124567 nonn %O A124567 0,3 %A A124567 _Paul D. Hanna_, Nov 07 2006