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%I #12 Nov 25 2018 12:26:00
%S 0,1,3,5,9,11,15,21,29,31,35,41,51,61,69,83,99,101,105,111,121,131,
%T 141,159,183,205,213,227,249,275,291,321,353,355,359,365,375,385,395,
%U 413,437,459,469,487,515,553,581,627,683,737,745,759,781,807
%N Toothpick sequence on hexagonal net starting from the vertex of a 60-degree wedge (see Comments lines for precise definition).
%C Toothpicks are connected by their endpoints. The toothpicks placed in north direction are prohibited. The sequence gives the number of toothpicks after n-th stage in the structure. A233971 (the first differences) give the number of toothpicks added at n-th stage.
%C First differs from A169780 at a(24).
%C First differs from both A233764 and A233780 at a(25).
%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/To#toothpick">Index entries for sequences related to toothpick sequences</a>
%Y Cf. A139250, A161206, A161830, A169780, A182632, A182634, A182634, A182840, A233760, A233764, A233780, A233971, A233972.
%K nonn
%O 0,3
%A _Omar E. Pol_, Dec 18 2013
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