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 A233761 Number of toothpicks or D-toothpicks added at n-th stage in the structure of the D-toothpick "wide" triangle of A233760. 3
 0, 1, 2, 2, 4, 2, 4, 6, 8, 2, 4, 6, 12, 14, 12, 14, 16, 2, 4, 6, 12, 14, 20, 22, 26, 22, 12, 18, 32, 38, 28, 30, 32, 2, 4, 6, 12, 14, 20, 22, 26, 22, 20, 30, 44, 62, 52, 46, 54, 38, 12, 18, 36, 46, 56, 62, 74, 74, 30, 42, 72, 86, 60, 62, 64, 2, 4, 6, 12 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,3 COMMENTS Essentially the first differences of A233760. LINKS N. J. A. Sloane, Catalog of Toothpick and Cellular Automata Sequences in the OEIS FORMULA a(2n) = A220521(2n); a(2n+1) = A220521(2n+1) - 2. EXAMPLE Written as an irregular triangle in which the row lengths is A011782 the sequence (starting from 1) begins: 1; 2; 2,4; 2,4,6,8; 2,4,6,12,14,12,14,16; 2,4,6,12,14,20,22,26,22,12,18,32,38,28,30,32; 2,4,6,12,14,20,22,26,22,20,30,44,62,52,46,54,38,12,18,36,46,56,62,74,74,30,42,72,86,60,62,64; Right border gives A000079. CROSSREFS Cf. A000079, A011782, A139251, A220501, A220521, A233760, A233763, A233781. Sequence in context: A233781 A233971 A170905 * A035096 A066675 A219433 Adjacent sequences:  A233758 A233759 A233760 * A233762 A233763 A233764 KEYWORD nonn,tabf AUTHOR Omar E. Pol, Dec 16 2013 STATUS approved

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Last modified March 23 10:55 EDT 2019. Contains 321424 sequences. (Running on oeis4.)