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A161421 First differences of A161420. 2
0, 1, 2, 2, 2, 4, 8, 6, 6, 8, 12, 8, 10, 10, 20, 18, 10, 16, 20, 8 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

COMMENTS

Number of V-toothpicks added at the n-th stage to the V-toothpick structure of A161420. See also A161206 and A161207.

Also it appears a(n) is also the number of toothpicks and D-toothpicks added at n-th stage to the H-toothpick structure of A161420. See also A182838 and A182839.

LINKS

Table of n, a(n) for n=0..19.

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

Index entries for sequences related to toothpick sequences

CROSSREFS

Cf. A139251, A161206, A161207, A161420, A161422, A182633, A182838, A182839.

Sequence in context: A286613 A229061 A278224 * A306337 A326022 A077943

Adjacent sequences:  A161418 A161419 A161420 * A161422 A161423 A161424

KEYWORD

more,nonn

AUTHOR

Omar E. Pol, Jun 10 2009, Dec 12 2010

STATUS

approved

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Last modified August 6 16:05 EDT 2020. Contains 336255 sequences. (Running on oeis4.)