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 A151555 G.f.: (1 + 2x ) * Prod_{ n >= 1} (1 + x^(2^n-1) + 2*x^(2^n)). 5
 1, 3, 4, 5, 5, 10, 12, 9, 5, 10, 13, 15, 20, 32, 32, 17, 5, 10, 13, 15, 20, 32, 33, 23, 20, 33, 41, 50, 72, 96, 80, 33, 5, 10, 13, 15, 20, 32, 33, 23, 20, 33, 41, 50, 72, 96, 81, 39, 20, 33, 41, 50, 72, 97, 89, 66, 73, 107, 132, 172, 240, 272, 192, 65, 5, 10, 13, 15, 20, 32, 33, 23 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 COMMENTS Contribution from Gary W. Adamson, May 25 2009: (Start) Convolved with A078008 signed (A151575) [1, 0, 2, -2, 6, -10, 22, -42, 86, -170,...] equals the toothpick sequence A153006: (1, 3, 6, 9, 13, 20, 28,...). (End) If A151550 is written as a triangle then the rows converge to this sequence. - N. J. A. Sloane, Jun 16 2009 LINKS N. J. A. Sloane, Table of n, a(n) for n = 0..16384 David Applegate, Omar E. Pol and N. J. A. Sloane, The Toothpick Sequence and Other Sequences from Cellular Automata, Congressus Numerantium, Vol. 206 (2010), 157-191. [There is a typo in Theorem 6: (13) should read u(n) = 4.3^(wt(n-1)-1) for n >= 2.] N. J. A. Sloane, Catalog of Toothpick and Cellular Automata Sequences in the OEIS EXAMPLE Contribution from Omar E. Pol, Jun 19 2009: (Start) May be written as a triangle: 1; 3; 4,5; 5,10,12,9; 5,10,13,15,20,32,32,17; 5,10,13,15,20,32,33,23,20,33,41,50,72,96,80,33; 5,10,13,15,20,32,33,23,20,33,41,50,72,96,81,39,20,33,41,50,72,97,89,66,73,... (End) CROSSREFS Cf. A139250, A151551, A151552, A151553, A151554, A151550, A152980, A153006. Cf. A078008 [From Gary W. Adamson, May 25 2009] Sequence in context: A278168 A130271 A139369 * A263728 A103606 A139794 Adjacent sequences:  A151552 A151553 A151554 * A151556 A151557 A151558 KEYWORD nonn AUTHOR N. J. A. Sloane, May 20 2009 STATUS approved

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Last modified June 7 05:20 EDT 2020. Contains 334837 sequences. (Running on oeis4.)