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 A008933 #19 Apr 22 2025 12:19:47 %S A008933 1,1,2,6,25,135,913,7499,73191,833597,10917343,162402263,2715430931, %T A008933 50576761471,1041203832858,23529845888598 %N A008933 Number of strictly increasing addition chains of length n. %H A008933 M. Torelli, <a href="http://dx.doi.org/10.1051/ita:2006017">Increasing integer sequences and Goldbach's conjecture</a>, RAIRO - Theoretical Informatics and Applications, vol.40, no.02 (April 2006), pp.107-121. %H A008933 David Bruce Wilson, <a href="http://dbwilson.com">Home page</a> [broken link] %K A008933 nonn,hard,more %O A008933 0,3 %A A008933 Mauro Torelli (torelli(AT)hermes.mc.dsi.unimi.it) %E A008933 More terms from David Bruce Wilson