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A304137 Number of nX4 0..1 arrays with every element unequal to 0, 2, 3 or 6 king-move adjacent elements, with upper left element zero. 1
1, 13, 9, 11, 20, 17, 25, 62, 59, 93, 220, 237, 381, 830, 991, 1601, 3236, 4185, 6769, 12894, 17715, 28661, 52204, 75029, 121397, 213918, 317815, 514233, 884532, 1346273, 2178313, 3682046, 5702891, 9227469, 15402748, 24157821, 39088173 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Column 4 of A304141.

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..210

FORMULA

Empirical: a(n) = 2*a(n-1) +2*a(n-3) -6*a(n-4) +3*a(n-6) for n>10

EXAMPLE

Some solutions for n=5

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

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

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

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

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

CROSSREFS

Cf. A304141.

Sequence in context: A301825 A300377 A300679 * A305043 A066552 A206609

Adjacent sequences:  A304134 A304135 A304136 * A304138 A304139 A304140

KEYWORD

nonn

AUTHOR

R. H. Hardin, May 07 2018

STATUS

approved

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Last modified January 25 19:09 EST 2020. Contains 331249 sequences. (Running on oeis4.)