A170857 a(0) = 0, a(1) = 1; a(2^i + j) = 3a(j) + 3a(j + 1) for 0 <= j < 2^i.

0, 1, 3, 12, 3, 12, 45, 45, 3, 12, 45, 45, 45, 171, 270, 144, 3, 12, 45, 45, 45, 171, 270, 144, 45, 171, 270, 270, 648, 1323, 1242, 441, 3, 12, 45, 45, 45, 171, 270, 144, 45, 171, 270, 270, 648, 1323, 1242, 441, 45, 171, 270, 270, 648, 1323, 1242, 567, 648, 1323, 1620, 2754

Offset

0,3

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: A358325 A288518 A069522 * A227106 A085296 A306364

Adjacent sequences: A170854 A170855 A170856 * A170858 A170859 A170860

Keyword

nonn

Author

N. J. A. Sloane, Jan 02 2010

Status

approved