A161831 First differences of A161830.

1, 2, 2, 4, 2, 4, 4, 8, 4, 4, 4, 8, 6, 8, 10, 18, 10, 4

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..18.

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, A139251, A160121, A160407, A161830, A161832, A161833.

Sequence in context: A001316 A285741 A364567 * A096865 A116466 A116467

Adjacent sequences: A161828 A161829 A161830 * A161832 A161833 A161834

Keyword

more,nonn

Author

Omar E. Pol, Jun 20 2009

Status

approved