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 A113731 #7 Sep 09 2017 10:31:43 %S A113731 1,1,2,6,27,225,5273,684632,1490340903 %N A113731 Number of terms in row n of A113730 when interpreted as a triangle. %C A113731 a(n+1) is also the row sum of row n of A113730. %Y A113731 Cf. A001462 (Golomb's sequence), A113723, A113725, A113676. %Y A113731 First differences of A113734. %K A113731 nonn,more %O A113731 1,3 %A A113731 _Floor van Lamoen_ and _Paul D. Hanna_, Nov 08 2005