A160158 Toothpick sequence starting from a segment of length 4 formed by two toothpicks.

0, 2, 4, 8, 16, 24, 28, 36, 48, 56, 64, 80, 104, 124, 136, 156, 176, 184, 192, 208, 232, 252, 268, 296, 328, 352, 384, 440, 508, 560, 600, 652, 688, 696, 704, 720, 744, 764, 780, 808, 840, 864, 896, 952, 1020, 1072, 1116, 1176, 1224, 1248, 1280, 1336, 1404

Offset: 0

Author

Omar E. Pol, May 29 2009

Keywords

• nonn

Comments

The sequence gives the number of toothpicks in the sieve after n-th stage.

Links

• 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, A160406, A160730, A160732, A160736, A160738, A160740.

Extensions

Extended beyond a(13) by R. J. Mathar, Jun 01 2009