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a(n) = A153006(n)*2.
2

%I #10 Feb 24 2021 02:48:18

%S 0,2,6,12,18,26,40,56,66,74,88,106,126,156,200,240,258,266,280,298,

%T 318,348,392,434,462,492,538,594,664,768,896,992,1026,1034,1048,1066,

%U 1086,1116,1160,1202,1230,1260,1306,1362,1432,1536,1664,1762,1806,1836,1882,1938

%N a(n) = A153006(n)*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>

%o (PARI) lista(nn) = concat(0, 2*Vec(x*((1+x)/(1-x))*prod(k=1, nn, 1+x^(2^k-1)+2*x^(2^k)) + O(x^nn))); \\ _Jinyuan Wang_, Mar 04 2020

%Y Toothpick sequence: A139250.

%Y Cf. A139251, A152980, A153006, A159794, A159795.

%K nonn

%O 0,2

%A _Omar E. Pol_, May 02 2009

%E More terms from _Jinyuan Wang_, Mar 04 2020