A161833 First differences of A161832.

1, 1, 2, 1, 2, 2, 4, 2, 2, 2, 4, 3, 4, 5, 9, 5, 2

Offset

1,3

Comments

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

Links

Table of n, a(n) for n=1..17.

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

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

Formula

a(n) = A161831(n+1)/2.

Crossrefs

Cf. A139251, A160121, A160407, A161830, A161831, A161832.

Sequence in context: A355639 A050378 A225216 * A294100 A139318 A205779

Adjacent sequences: A161830 A161831 A161832 * A161834 A161835 A161836

Keyword

more,nonn

Author

Omar E. Pol, Jun 20 2009

Status

approved