A182635 - OEIS

%I #22 Feb 24 2021 02:48:19

%S 0,1,2,4,4,4,8,12,8,4,8,16,20,16,20,28,16,4,8,16,20,20,28,44,44,24,20,

%T 40,56,48,52,64,32,4,8,16,20,20,28,44,44,28,28,52,76,76,76

%N Number of toothpicks added at n-th stage to the toothpick structure of A182634.

%C First differences of A182634.

%C First differs from A139251 at a(11).

%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>

%H <a href="/index/To#toothpick">Index entries for sequences related to toothpick sequences</a>

%H <a href="/index/Ce#cell">Index entries for sequences related to cellular automata</a>

%F a(n) = A182633(n)/3.

%e Contribution from _Omar E. Pol_, Dec 06 2012 (Start):

%e When written as an irregular triangle begins:

%e 0;

%e 1;

%e 2;

%e 4,4;

%e 4,8,12,8;

%e 4,8,16,20,16,20,28,16;

%e 4,8,16,20,20,28,44,44,24,20,40,56,48,52,64,32;

%e 4,8,16,20,20,28,44,44,28,28,52,76,76,76,...

%e (End)

%Y Cf. A139250, A139251, A160121, A161207, A161645, A182633, A182634, A194445.

%K nonn,more

%O 0,3

%A _Omar E. Pol_, Dec 08 2010