0,3

First differences of A151895. See that entry for much more information.

David Applegate, Table of n, a(n) for n = 0..250

David Applegate, The movie version

David Applegate, Illustration of first 10 generations

David Applegate, Illustration of first 20 generations

David Applegate, Illustration of first 32 generations

David Applegate, Illustration of first 64 generations

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

N. J. A. Sloane, Illustration of initial terms (concentrating on a 90 degree sector)

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

We do not know of a recurrence or generating function.

Cf. A151895, A139250.

Sequence in context: A219578 A219373 A151906 * A267191 A170897 A217771

Adjacent sequences: A151893 A151894 A151895 * A151897 A151898 A151899

nonn

David Applegate and N. J. A. Sloane, Jul 30 2009

Revised by David Applegate and N. J. A. Sloane, Jan 21 2016.

approved