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 A170869 a(0) = 1, a(1) = 2; a(2^i + j) = 3a(j) + 2a(j + 1) for 0 <= j < 2^i. 0
 1, 2, 7, 20, 7, 20, 61, 74, 7, 20, 61, 74, 61, 182, 331, 236, 7, 20, 61, 74, 61, 182, 331, 236, 61, 182, 331, 344, 547, 1208, 1465, 722, 7, 20, 61, 74, 61, 182, 331, 236, 61, 182, 331, 344, 547, 1208, 1465, 722, 61, 182, 331, 344, 547, 1208, 1465, 830, 547, 1208, 1681, 2126 (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 Sequence in context: A137990 A056650 A182169 * A162355 A045858 A160677 Adjacent sequences:  A170866 A170867 A170868 * A170870 A170871 A170872 KEYWORD nonn AUTHOR N. J. A. Sloane, Jan 02 2010 STATUS approved

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Last modified December 6 13:05 EST 2021. Contains 349563 sequences. (Running on oeis4.)