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A160158
Toothpick sequence starting from a segment of length 4 formed by two toothpicks.
5
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
0,2
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.]
KEYWORD
nonn
AUTHOR
Omar E. Pol, May 29 2009
EXTENSIONS
Extended beyond a(13) by R. J. Mathar, Jun 01 2009
STATUS
approved