A151885 Similar to the original toothpick sequence A139250, except that the rule is now: a toothpick changes state if its midpoint is adjacent to exactly one ON toothpick.
0, 1, 3, 5, 11, 5, 15, 17, 39, 5, 15, 25, 55, 17, 51, 61, 139, 5, 15, 25, 55, 25, 75, 85, 195, 17, 51, 85, 187, 61, 183, 217, 495, 5, 15, 25, 55, 25, 75, 85, 195, 25, 75, 125, 275, 85, 255, 305, 695, 17, 51, 85, 187, 85, 255, 289, 663
Offset: 0
Keywords
Links
- Nathaniel Johnston, Table of n, a(n) for n = 0..925
- 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.]
- Nathaniel Johnston, C program for computing terms of A151885-A151888
- N. J. A. Sloane, Catalog of Toothpick and Cellular Automata Sequences in the OEIS
- N. J. A. Sloane, Illustration of first 8 generations
Formula
a(n) = a(n-1) + A151888(n).
Extensions
Terms after a(8) from Nathaniel Johnston, Apr 02 2011
Comments