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A160408 Toothpick pyramid (see Comments lines for definition). 7


%S 0,1,2,4,8,12,16,20,24,32,48,64,72,76,80,88

%N Toothpick pyramid (see Comments lines for definition).

%C The toothpick pyramid is a three-dimensional version of the toothpick triangle A160406.

%C The sequence gives the number of toothpicks after n rounds. A160409 (the first differences) gives the number added at the n-th round.

%C See also the entry A139250 for more information about the toothpick sequences.

%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), 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, A139251, A160160, A160406, A160407, A160409.

%K more,nonn

%O 0,3

%A _Omar E. Pol_, May 23 2009, Jun 06 2009

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Last modified August 12 12:15 EDT 2020. Contains 336439 sequences. (Running on oeis4.)