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A170887 First differences of toothpick sequence A170886. 4
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 (list; graph; refs; listen; history; text; internal format)
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 A008238 A218870

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

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Last modified January 15 20:47 EST 2019. Contains 319184 sequences. (Running on oeis4.)