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