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A151921 Net gain in number of ON cells at stage n of the cellular automaton described in A079317. 2
0, 1, 4, 0, 12, -8, 20, -8, 44, -40, 52, -40, 76, -64, 100, -64, 172, -168, 180, -168, 204, -192, 228, -192, 300, -288, 324, -288, 396, -360, 468, -360, 684, -680, 692, -680, 716, -704, 740, -704, 812, -800, 836, -800, 908, -872, 980, -872, 1196 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

COMMENTS

Start with cell (0,0) ON; at each succeeding stage the cells that share exactly one edge with an active cell change their state.

LINKS

Table of n, a(n) for n=0..48.

David Applegate, Omar E. Pol and N. J. A. Sloane, The Toothpick Sequence and Other Sequences from Cellular Automata

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

FORMULA

If n is even, a(n) = A079315(n) = A151914(n/2); if n is odd, a(n) = A147582((n+1)/2) - A151914((n-1)/2).

First differences of A079317.

CROSSREFS

Cf. A079317, A079315, A139250, A151914, A147582.

Sequence in context: A273795 A273858 A273485 * A273838 A273761 A273424

Adjacent sequences:  A151918 A151919 A151920 * A151922 A151923 A151924

KEYWORD

sign

AUTHOR

N. J. A. Sloane, Aug 05 2009, Aug 06 2009

STATUS

approved

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Last modified February 20 07:12 EST 2018. Contains 299359 sequences. (Running on oeis4.)