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A188986 Number of n X 3 binary arrays without the pattern 0 0 1 antidiagonally or horizontally. 1
7, 49, 295, 1793, 10871, 65937, 399911, 2425505, 14710935, 89223345, 541148807, 3282123457, 19906418039, 120734483153, 732267120743, 4441275782369, 26936796718423, 163374456576241, 990882967287879, 6009807624994561 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 3 of A188992.

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..200

FORMULA

Empirical: a(n) = 6*a(n-1) +a(n-2) -4*a(n-3) +2*a(n-4).

Empirical g.f.: x*(7 + 7*x - 6*x^2 + 2*x^3) / ((1 + x)*(1 - 7*x + 6*x^2 - 2*x^3)). - Colin Barker, May 01 2018

EXAMPLE

Some solutions for 4 X 3:

..1..0..0....0..1..0....0..0..0....1..1..0....0..0..0....1..0..0....1..0..0

..1..1..1....0..1..0....0..1..0....1..0..0....0..1..1....1..0..1....1..0..0

..0..0..0....1..1..0....1..1..1....0..1..1....1..0..0....0..1..1....0..0..0

..0..1..1....1..1..0....0..0..0....0..1..1....1..0..0....1..0..0....0..1..1

CROSSREFS

Cf. A188992.

Sequence in context: A213295 A189258 A188748 * A146884 A113235 A294261

Adjacent sequences:  A188983 A188984 A188985 * A188987 A188988 A188989

KEYWORD

nonn

AUTHOR

R. H. Hardin, Apr 15 2011

STATUS

approved

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Last modified November 27 20:49 EST 2021. Contains 349395 sequences. (Running on oeis4.)