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%I #9 Feb 24 2021 02:48:19
%S 1,1,1,2,2,1,1,2,2,2,4,6,4,1,1,2,2,2,4,6,4,2,4,6,6,8,14,16,8,1,1,2,2,
%T 2,4,6,4,2,4,6,6,8,14,16,8,2,4,6,6,8,14,16,10,8,14,18,20,30,44,40,16,
%U 1,1,2,2,2,4,6,4,2,4,6,6,8,14,16
%N a(n) = A139560(n+1)/2.
%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>
%Y Cf. A139250, A139252, A139560.
%K nonn
%O 1,4
%A _Omar E. Pol_, Dec 09 2009
%E Terms after a(27) from _Nathaniel Johnston_, Mar 29 2011