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%I #10 Feb 24 2021 02:48:19
%S 4,13,7,13,43,34,10,13,43,34,46,142,145,64,13,13,43,34,46,142,145,64,
%T 49,142,145,172,472,577,337,103,16,13,43,34,46,142,145,64,49,142,145,
%U 172,472,577,337,103,52,142,145,172,472,577,337,211,475,577,661,1588,2203,1588
%N G.f.: Product_{k>=0} (1 + 3x^(2^k-1) + x^(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 0,1
%A _N. J. A. Sloane_, Jan 02 2010