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A170854 a(0) = 0, a(1) = 1; a(2^i + j) = 3a(j) + 2a(j + 1) for 0 <= j < 2^i. 2

%I #6 Feb 24 2021 02:48:19

%S 0,1,2,7,2,7,20,25,2,7,20,25,20,61,110,79,2,7,20,25,20,61,110,79,20,

%T 61,110,115,182,403,488,241,2,7,20,25,20,61,110,79,20,61,110,115,182,

%U 403,488,241,20,61,110,115,182,403,488,277,182,403,560,709,1352,2185,1946,727,2

%N a(0) = 0, a(1) = 1; a(2^i + j) = 3a(j) + 2a(j + 1) for 0 <= j < 2^i.

%H David Applegate, Omar E. Pol and N. J. A. Sloane, <a href="/A000695/a000695_1.pdf">The Toothpick Sequence and Other Sequences from Cellular Automata</a>, 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.]

%H N. J. A. Sloane, <a href="/wiki/Catalog_of_Toothpick_and_CA_Sequences_in_OEIS">Catalog of Toothpick and Cellular Automata Sequences in the OEIS</a>

%K nonn

%O 0,3

%A _N. J. A. Sloane_, Jan 02 2010

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Last modified April 19 12:14 EDT 2024. Contains 371792 sequences. (Running on oeis4.)