A161430 Fractal triangle whose virtual skeleton is a polyedge as the Y-toothpick structure of A160120.

0, 9, 33, 57, 123, 147

Offset

0,2

Comments

Number of ON states after n generations of cellular automaton based on the infinite triangular grid.

Links

Table of n, a(n) for n=0..5.

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, A161341, A161342, A161343.

Sequence in context: A075812 A256868 A146262 * A175369 A046895 A165392

Adjacent sequences: A161427 A161428 A161429 * A161431 A161432 A161433

Keyword

more,nonn

Author

Omar E. Pol, Jun 17 2009

Status

approved