A161427 First differences of A161426.

1, 3, 3, 7, 5, 7, 9, 17, 11, 7

Offset

1,2

Comments

Number of Y-toothpicks added to the sieve at the n-th round.

Links

Table of n, a(n) for n=1..10.

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

David Applegate, The movie version

Crossrefs

Cf. A139251, A152980, A160121, A161426, A161831.

Sequence in context: A086799 A218388 A308340 * A365212 A098688 A129266

Adjacent sequences: A161424 A161425 A161426 * A161428 A161429 A161430

Keyword

more,nonn

Author

Omar E. Pol and David Applegate, Jun 20 2009

Status

approved