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 A222172 #18 Nov 25 2013 15:15:10 %S A222172 0,1,2,3,5,8,10,11,13,17,21,24,29,36,40,41,43,47,53,61 %N A222172 Total number of ON states after n generations of cellular automaton based on pentagons starting near of the vertex of an infinite 36-degree wedge. %C A222172 The sequence gives the number of pentagons in the structure after n-th stage. A222173 (the first differences) gives the number of pentagons added at n-th stage. %C A222172 Also P-toothpick sequence starting near of the vertex of an infinite 36-degree wedge, since each pentagon can be replaced by a P-toothpick. %C A222172 For more information see A222180. %C A222172 First differs from A153000 at a(9). %H A222172 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 A222172 <a href="/index/To#toothpick">Index entries for sequences related to toothpick sequences</a> %F A222172 a(n) = (((A222180(n+2) - 1)/5) - 1)/2 = (A222176(n+1) - 1)/2. %F A222172 a(n) = (A222180(n+2) - 6)/10. - _Omar E. Pol_, Nov 24 2013 %Y A222172 Cf. A139250, A153000, A222173, A222176, A222180. %K A222172 nonn,more %O A222172 0,3 %A A222172 _Omar E. Pol_, Mar 21 2013 %E A222172 Name improved by _Omar E. Pol_, Nov 24 2013