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 A294980 #24 Mar 11 2019 20:21:47 %S A294980 0,1,4,10,16,22,40,58,76,82 %N A294980 a(n) is the total number of elements after n-th stage in a hybrid cellular automaton formed by Y-toothpicks and V-toothpicks (see Comments lines for precise definition). %C A294980 We are on the infinite triangular grid. %C A294980 At stage 0 there are no elements in the structure, so a(0) = 0. %C A294980 If n is odd at n-th stage we add Y-toothpicks to the structure. %C A294980 If n is a positive even number at n-th stage we add V-toothpicks to the structure. %C A294980 a(n) is the total number of Y-toothpicks and V-toothpicks after n-th stages. %C A294980 A294981(n) gives the number of elements added to the structure at n-th stage. %C A294980 The "word" of this cellular automaton is "ab". For further information about the word of cellular automata see A296612. - _Omar E. Pol_, Mar 05 2019 %H A294980 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 A294980 <a href="/index/Ce#cell">Index entries for sequences related to cellular automata</a> %H A294980 <a href="/index/To#toothpick">Index entries for sequences related to toothpick sequences</a> %Y A294980 Cf. A139250, A160120 (Y-toothpicks), A161206 (V-toothpicks), A294981 (first differences), A296612. %Y A294980 For other hybrid cellular automata see: A289840, A290220, A294020, A294962. %K A294980 nonn,more %O A294980 0,3 %A A294980 _Omar E. Pol_, Nov 12 2017