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 A151672 G.f.: Product_{k>=0} (1 + 4*x^(3^k)). 18
 1, 4, 0, 4, 16, 0, 0, 0, 0, 4, 16, 0, 16, 64, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 4, 16, 0, 16, 64, 0, 0, 0, 0, 16, 64, 0, 64, 256, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 4, 16, 0, 16, 64, 0, 0, 0, 0, 16, 64, 0, 64, 256, 0 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 LINKS 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 CROSSREFS For generating functions Product_{k>=0} (1 + a*x^(b^k)) for the following values of (a,b) see: (1,2) A000012 and A000027, (1,3) A039966 and A005836, (1,4) A151666 and A000695, (1,5) A151667 and A033042, (2,2) A001316, (2,3) A151668, (2,4) A151669, (2,5) A151670, (3,2) A048883, (3,3) A117940, (3,4) A151665, (3,5) A151671, (4,2) A102376, (4,3) A151672, (4,4) A151673, (4,5) A151674. Sequence in context: A281297 A058536 A154854 * A058493 A112149 A087736 Adjacent sequences:  A151669 A151670 A151671 * A151673 A151674 A151675 KEYWORD nonn AUTHOR N. J. A. Sloane, May 30 2009 STATUS approved

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Last modified April 17 14:32 EDT 2021. Contains 343063 sequences. (Running on oeis4.)