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 A233764 Number of toothpicks and D-toothpicks after n-th stage in a D-toothpick "wide" triangle (see Comments lines for definition). 3

%I

%S 0,1,3,5,9,11,15,21,29,31,35,41,51,61,69,83,99,101,105,111,121,131,

%T 141,159,183,201,209,223,245,271,287,317,349,351,355,361,371,381,391,

%U 409,433,451,461,479,507,545,575,625,679,713,721,735,757,783

%N Number of toothpicks and D-toothpicks after n-th stage in a D-toothpick "wide" triangle (see Comments lines for definition).

%C The D-toothpicks placed in northwest or northeast direction both are prohibited. Note that due this rule there are substructures with broken symmetry, for instance a(44) = 507, not 509. For another version without broken symmetry see A233780.

%C A233765 (the first differences) gives the number of toothpicks or D-toothpicks added at n-th stage.

%C First differs from A169780 at a(24).

%C First differs from A233970 at a(25).

%C First differs from A233780 at a(44).

%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, A169780, A220500, A220520, A231348, A233765, A233780, A233970.

%K nonn

%O 0,3

%A _Omar E. Pol_, Dec 16 2013

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Last modified April 24 18:03 EDT 2019. Contains 322430 sequences. (Running on oeis4.)