A170887 First differences of toothpick sequence A170886.

0, 1, 2, 2, 2, 4, 6, 6, 6, 8, 12, 6, 8, 12, 18, 14, 14, 20, 20, 6, 8, 12, 18, 14, 16, 24, 26, 16, 24, 38, 46, 38, 42, 52, 36, 6, 8, 12, 18, 14, 16, 24, 26, 16, 24, 38, 46, 38, 44, 56, 42, 16, 24, 38, 46, 40, 52, 70, 64, 52, 82, 118, 126, 114, 130, 132, 68, 6, 8, 12, 18, 14, 16, 24

Offset

0,3

Comments

Number of toothpicks added at n-th stage to the toothpick structure of A170886. - Omar E. Pol, Jan 31 2013

Links

Table of n, a(n) for n=0..73.

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

Example

From Omar E. Pol, Jan 30 2013: (Start)
If written as an irregular triangle in which rows 0..3 have length 1, it appears that row j has length 2^(j-4), if j >= 4. - Omar E. Pol, Jan 31 2013
0;
1;
2;
2;
2;
4,6;
6,6,8,12;
6,8,12,18,14,14,20,20;
6,8,12,18,14,16,24,26,16,24,38,46,38,42,52,36;
6,8,12,18,14,16,24,26,16,24,38,46,38,44,56,42,16,24,38,46,40,52,70,64,52,82,118,126,114,130,132,68;
6,8,12,18,14,16,24,...
(End)

Crossrefs

Cf. A139250, A139251, A160407, A170886, A170889, A170891, A170893.

Sequence in context: A248781 A236840 A182539 * A103265 A341695 A008238

Adjacent sequences: A170884 A170885 A170886 * A170888 A170889 A170890

Keyword

nonn,tabf

Author

Omar E. Pol, Jan 09 2010

Extensions

More terms from R. J. Mathar, Jan 25 2010

Status

approved