A170869 a(0) = 1, a(1) = 2; a(2^i + j) = 3a(j) + 2a(j + 1) for 0 <= j < 2^i.

1, 2, 7, 20, 7, 20, 61, 74, 7, 20, 61, 74, 61, 182, 331, 236, 7, 20, 61, 74, 61, 182, 331, 236, 61, 182, 331, 344, 547, 1208, 1465, 722, 7, 20, 61, 74, 61, 182, 331, 236, 61, 182, 331, 344, 547, 1208, 1465, 722, 61, 182, 331, 344, 547, 1208, 1465, 830, 547, 1208, 1681, 2126

Offset

0,2

Links

Table of n, a(n) for n=0..59.

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

Sequence in context: A056650 A182169 A373765 * A162355 A045858 A160677

Adjacent sequences: A170866 A170867 A170868 * A170870 A170871 A170872

Keyword

nonn

Author

N. J. A. Sloane, Jan 02 2010

Status

approved