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A151779 a(1)=1; for n > 1, a(n)=6*5^{wt(n-1)-1}. 11
1, 6, 6, 30, 6, 30, 30, 150, 6, 30, 30, 150, 30, 150, 150, 750, 6, 30, 30, 150, 30, 150, 150, 750, 30, 150, 150, 750, 150, 750, 750, 3750, 6, 30, 30, 150, 30, 150, 150, 750, 30, 150, 150, 750, 150, 750, 750, 3750, 30, 150, 150, 750, 150, 750, 750, 3750, 150, 750, 750, 3750 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Number of cells turned ON in n-th generation of cellular automaton based on Z^3 lattice in the same way that A147562 is based on the Z^2 lattice. Here each cell has six neighbors.

LINKS

Charles R Greathouse IV, Table of n, a(n) for n = 1..10000

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

MAPLE

wt := proc(n) local w, m, i; w := 0; m := n; while m > 0 do i := m mod 2; w := w+i; m := (m-i)/2; od; w; end:

f:=d->[seq((2*d)*(2*d-1)^(wt(n-1)-1), n=2..120)];

f2:=d->[1, op(f(d))];

f2(3);

PROG

(PARI) a(n)=6*5^(hammingweight(n-1)-1)\1 \\ Charles R Greathouse IV, Mar 07 2015

CROSSREFS

Cf. A147582, A151780, A151781, A151782.

Sequence in context: A253066 A016725 A267651 * A255462 A066714 A054436

Adjacent sequences:  A151776 A151777 A151778 * A151780 A151781 A151782

KEYWORD

nonn,easy

AUTHOR

N. J. A. Sloane, Jun 25 2009

STATUS

approved

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Last modified December 12 16:06 EST 2018. Contains 318077 sequences. (Running on oeis4.)