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 A170856 a(0) = 0, a(1) = 1; a(2^i + j) = 2a(j) + 3a(j + 1) for 0 <= j < 2^i. 1
 0, 1, 3, 11, 3, 11, 39, 31, 3, 11, 39, 31, 39, 139, 171, 71, 3, 11, 39, 31, 39, 139, 171, 71, 39, 139, 171, 179, 495, 791, 555, 151, 3, 11, 39, 31, 39, 139, 171, 71, 39, 139, 171, 179, 495, 791, 555, 151, 39, 139, 171, 179, 495, 791, 555, 259, 495, 791, 879, 1843, 3363, 3247 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,3 LINKS Robert Israel, Table of n, a(n) for n = 0..10000 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 MAPLE f:= proc(n) option remember; local j;    j:= n - 2^ilog2(n);    2*procname(j)+3*procname(j+1); end proc: f(0):= 0: f(1):= 1: map(f, [\$0..100]); # Robert Israel, Jun 12 2018 CROSSREFS Sequence in context: A244237 A238683 A303114 * A176781 A226625 A210610 Adjacent sequences:  A170853 A170854 A170855 * A170857 A170858 A170859 KEYWORD nonn,look AUTHOR N. J. A. Sloane, Jan 02 2010 STATUS approved

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Last modified January 18 13:05 EST 2019. Contains 319271 sequences. (Running on oeis4.)