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 A250300 #18 Jan 17 2015 13:29:02 %S A250300 0,3,6,12,24,36,42,54,72,90,108,126,162,198,210,234,264,282,300,324, %T A250300 366,420,462,498,558,624,678,726,816,906,936,990,1044,1062,1080,1104, %U A250300 1146,1200,1242,1284,1350,1428,1506,1584,1698,1848,1950,2022,2130 %N A250300 Number of ON states after n generations of cellular automaton based on triangles (compare A161644). %C A250300 The same rules as A161644 but here we start with three ON cells which share only one vertex. %H A250300 N. J. A. Sloane, <a href="/wiki/Catalog_of_Toothpick_and_CA_Sequences_in_OEIS">Catalog of Toothpick and Cellular Automata Sequences in the OEIS</a> %H A250300 <a href="/index/Ce#cell">Index entries for sequences related to cellular automata</a> %Y A250300 Cf. A139250, A147562, A151723, A160120, A161644, A182632, A253770. %K A250300 nonn %O A250300 0,2 %A A250300 _Omar E. Pol_, Jan 15 2015