

A233764


Number of toothpicks and Dtoothpicks after nth stage in a Dtoothpick "wide" triangle (see Comments lines for definition).


3



0, 1, 3, 5, 9, 11, 15, 21, 29, 31, 35, 41, 51, 61, 69, 83, 99, 101, 105, 111, 121, 131, 141, 159, 183, 201, 209, 223, 245, 271, 287, 317, 349, 351, 355, 361, 371, 381, 391, 409, 433, 451, 461, 479, 507, 545, 575, 625, 679, 713, 721, 735, 757, 783
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OFFSET

0,3


COMMENTS

The Dtoothpicks 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.
A233765 (the first differences) gives the number of toothpicks or Dtoothpicks added at nth stage.
First differs from A169780 at a(24).
First differs from A233970 at a(25).
First differs from A233780 at a(44).


LINKS

Table of n, a(n) for n=0..53.
N. J. A. Sloane, Catalog of Toothpick and Cellular Automata Sequences in the OEIS
Index entries for sequences related to toothpick sequences


CROSSREFS

Cf. A139250, A169780, A220500, A220520, A231348, A233765, A233780, A233970.
Sequence in context: A199407 A261141 A283594 * A233780 A233970 A169780
Adjacent sequences: A233761 A233762 A233763 * A233765 A233766 A233767


KEYWORD

nonn


AUTHOR

Omar E. Pol, Dec 16 2013


STATUS

approved



