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 A086607 #5 Apr 18 2012 06:16:19 %S A086607 1,2,9,32,140,630,2870,13256,61389,286710,1346004,6351516,30088071, %T A086607 142997456,681498600,3255674016,15585877627,74752865964,359121640259, %U A086607 1727811098500,8323912135434,40149494252802,193868148499388,937055479499472,4533362484840700 %N A086607 Main diagonal of triangle A086606: the n-th term of the n-th self-convolution of the sequence formed by flattening triangle A086606. %Y A086607 Cf. A086606, A086608 (row sums). %K A086607 nonn %O A086607 1,2 %A A086607 _Paul D. Hanna_, Jul 23 2003