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A170884
In the toothpick structure of A160160, the number of nodes occupied after n steps, assuming that the toothpicks have length 2.
4
0, 3, 7, 15, 27, 39, 51, 67, 99, 155, 223, 263, 283, 299, 331, 387, 467, 555, 659, 811, 1067, 1443, 1831, 1995, 2059, 2083, 2123, 2179, 2259, 2347, 2451, 2603, 2859, 3235, 3659, 3955, 4211, 4483, 4899, 5451
OFFSET
0,2
COMMENTS
See A170885 for the first differences.
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.]
CROSSREFS
Sequence in context: A213215 A353578 A324719 * A182836 A360452 A097080
KEYWORD
nonn
AUTHOR
EXTENSIONS
a(7)-a(39) from Nathaniel Johnston, Nov 13 2010
STATUS
approved