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%I #33 Apr 16 2018 09:08:52
%S 0,2,8,14,20,26,44,50,68,86,104,110,128,158,176,206,260,278,320,350,
%T 392,410,452,494,548,614
%N Snowflake (or E-toothpick) sequence of the second kind (see Comments lines for definition).
%C This has essentially the same rules as the snowflake sequence A161330, but here there is an additional rule: there are no E-toothpicks of the same generation that share the endpoint of two parallel components.
%C The structure is lighter than the structure of A161330 from which differs at a(7).
%C Note that, on the infinite triangular grid, an E-toothpick can be represented as a polyedge with three components. In this case, at the n-th round, the structure is a polyedge with 3*a(n) components.
%C An E-toothpick looks like a bird's footprint (or more generally a dinosaur's footprint).
%C a(n) gives the number of E-toothpicks in the structure after n rounds.
%C A294961(n) is the number of E-toothpicks added at the n-th round, n >= 1. - _Omar E. Pol_, Apr 15 2018
%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 Another version of A161330.
%Y Cf. A139250, A160120, A161328, A294961 (first differences).
%K nonn,more
%O 0,2
%A _Omar E. Pol_, Nov 12 2017