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A161418 Number of triangles in the Y-toothpick structure after n rounds. 5
0, 0, 0, 0, 6, 6, 12, 12, 24, 30 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,5

LINKS

Table of n, a(n) for n=0..9.

David Applegate, Omar E. Pol and N. J. A. Sloane, The Toothpick Sequence and Other Sequences from Cellular Automata, 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.]

N. J. A. Sloane, Catalog of Toothpick and Cellular Automata Sequences in the OEIS

CROSSREFS

Cf. A139250, A160120, A160124, A161419, A161828, A161836.

Sequence in context: A315784 A315785 A127402 * A124691 A315786 A112437

Adjacent sequences:  A161415 A161416 A161417 * A161419 A161420 A161421

KEYWORD

more,nonn

AUTHOR

Omar E. Pol, Jun 21 2009

STATUS

approved

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Last modified December 6 14:15 EST 2019. Contains 329806 sequences. (Running on oeis4.)