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A304265 Number of nX3 0..1 arrays with every element unequal to 0, 1, 5 or 8 king-move adjacent elements, with upper left element zero. 1
3, 3, 6, 10, 19, 37, 67, 124, 235, 436, 808, 1513, 2821, 5245, 9784, 18247, 33982, 63334, 118075, 220021, 410023, 764248, 1424311, 2654380, 4947124, 9220057, 17183197, 32024569, 59684740, 111234331, 207308038, 386362258, 720065251, 1341989365 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 3 of A304270.

LINKS

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

FORMULA

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

EXAMPLE

Some solutions for n=5

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

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

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

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

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

CROSSREFS

Cf. A304270.

Sequence in context: A300301 A031504 A298164 * A049871 A049924 A049926

Adjacent sequences:  A304262 A304263 A304264 * A304266 A304267 A304268

KEYWORD

nonn

AUTHOR

R. H. Hardin, May 09 2018

STATUS

approved

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Last modified December 7 09:15 EST 2021. Contains 349574 sequences. (Running on oeis4.)