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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
 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 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,3 COMMENTS 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. A233765 (the first differences) gives the number of toothpicks or D-toothpicks added at n-th stage. First differs from A169780 at a(24). First differs from A233970 at a(25). First differs from A233780 at a(44). LINKS N. J. A. Sloane, Catalog of Toothpick and Cellular Automata Sequences in the OEIS 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

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Last modified October 15 01:40 EDT 2019. Contains 328025 sequences. (Running on oeis4.)