%I
%S 4,15,21,21,57,108,90,39,57,108,126,234,495,594,351,93,57,108,126,234,
%T 495,594,387,288,495,702,1080,2187,3267,2835,1296,255,57,108,126,234,
%U 495,594,387,288,495,702,1080,2187,3267,2835,1332,450,495,702,1080,2187,3267,2943
%N G.f.: Prod_{k >= 0} (1 + 3x^(2^k1) + 3x^(2^k)).
%H David Applegate, Omar E. Pol and N. J. A. Sloane, <a href="http://neilsloane.com/doc/tooth.pdf">The Toothpick Sequence and Other Sequences from Cellular Automata</a>, Congressus Numerantium, Vol. 206 (2010), 157191. [There is a typo in Theorem 6: (13) should read u(n) = 4.3^(wt(n1)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
