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 A160809 First differences of A160808. 2
 1, 2, 4, 4, 4, 8, 12, 4, 1, 2, 3, 3, 4, 7, 8, 1, 2, 3, 3, 4, 5, 7, 5, 3, 5, 7, 8, 11, 13, 17, 12, 4, 5, 8, 7, 9, 5, 7, 9, 8, 4, 8, 8, 7, 8, 13, 14, 10, 8, 12, 11, 13, 13, 17, 16, 11, 8, 15, 13, 14, 19, 26, 21, 5, 7 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS Number of toothpicks added to the spiral at the n-th stage. LINKS Nathaniel Johnston, Table of n, a(n) for n = 1..254 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 Cf. A000045, A139250, A139251, A160426, A160427, A160800, A160801, A160802, A160803, A160808. Sequence in context: A170893 A194445 A220525 * A139251 A342272 A182635 Adjacent sequences: A160806 A160807 A160808 * A160810 A160811 A160812 KEYWORD nonn AUTHOR Omar E. Pol, May 26 2009 EXTENSIONS Terms after a(16) from Nathaniel Johnston, Mar 30 2011 STATUS approved

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Last modified December 11 02:45 EST 2023. Contains 367717 sequences. (Running on oeis4.)