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 A170839 G.f.: Product_{k>=1} (1 + x^(2^k-1) + 3x^(2^k)). 0

%I

%S 1,1,3,1,4,6,9,1,4,6,10,7,18,27,27,1,4,6,10,7,18,27,28,7,18,28,37,39,

%T 81,108,81,1,4,6,10,7,18,27,28,7,18,28,37,39,81,108,82,7,18,28,37,39,

%U 81,109,91,39,82,121,150,198,351,405,243,1,4,6,10,7,18,27,28,7,18,28,37,39,81

%N G.f.: Product_{k>=1} (1 + x^(2^k-1) + 3x^(2^k)).

%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 May 8 05:46 EDT 2021. Contains 343653 sequences. (Running on oeis4.)