A187213 Number of Q-toothpicks added at n-th stage to the structure of A187212.

0, 1, 2, 2, 4, 4, 8, 10, 8, 4, 8, 12, 12, 16, 28, 30, 16, 4, 8, 12, 12, 16, 28, 32, 20, 16, 28, 36, 40, 60, 88, 78, 32, 4, 8, 12, 12, 16, 28, 32, 20, 16, 28, 36, 40, 60, 88, 80, 36, 16, 28, 36, 40, 60, 88, 84, 56, 60, 92, 112

Offset: 0

Author

Omar E. Pol, Mar 22 2011

Keywords

• nonn

Comments

Essentially the first differences of A187212.

Examples

			Contribution from Omar E. Pol, Mar 29 2011 (Start):
If written as a triangle begins:
0,
1,
2,
2,4,
4,8,10,8,
4,8,12,12,16,28,30,16,
4,8,12,12,16,28,32,20,16,28,36,40,60,88,78,32,
(End)
		

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.]
• Nathaniel Johnston, The Q-Toothpick Cellular Automaton
• N. J. A. Sloane, Catalog of Toothpick and Cellular Automata Sequences in the OEIS

Crossrefs

Cf. A139250, A139251, A187211, A187212, A187221.

Formula

It appears that if n = 2^k - 1, for k >= 2, then a(n) = A139251(n) - 2 otherwise a(n) = A139251(n). - Omar E. Pol, Mar 30 2011

Extensions

Terms after a(24) from Nathaniel Johnston, Mar 28 2011