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A220521 Number of toothpicks or D-toothpicks added at n-th stage in the toothpick structure of A220520. 12
0, 1, 2, 4, 4, 4, 4, 8, 8, 4, 4, 8, 12, 16, 12, 16, 16, 4, 4, 8, 12, 16, 20, 24, 26, 24, 12, 20, 32, 40, 28, 32, 32, 4, 4, 8, 12, 16, 20, 24, 26, 24, 20, 32, 44, 64, 52, 48, 54, 40, 12, 20, 36, 48, 56, 64, 74, 76, 30, 44, 72, 88, 60, 64, 64, 4, 4, 8, 12 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

COMMENTS

Essentially the first differences of A220520. First differs from A194441 at a(14).

LINKS

Table of n, a(n) for n=0..68.

N. J. A. Sloane, Catalog of Toothpick and Cellular Automata Sequences in the OEIS

Index entries for sequences related to toothpick sequences

EXAMPLE

Written as an irregular triangle:

0;

1;

2;

4,4;

4,4,8,8;

4,4,8,12,16,12,16,16;

4,4,8,12,16,20,24,26,24,12,20,32,40,28,32,32;

4,4,8,12,16,20,24,26,24,20,32,44,64,52,48,54,40,12,20,...

CROSSREFS

Cf. A139250, A139251, A194441, A194443.

Sequence in context: A235863 A220495 A194441 * A236680 A162798 A088650

Adjacent sequences:  A220518 A220519 A220520 * A220522 A220523 A220524

KEYWORD

nonn,less

AUTHOR

Omar E. Pol, Dec 15 2012

STATUS

approved

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Last modified November 15 08:37 EST 2019. Contains 329144 sequences. (Running on oeis4.)