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A304664 Number of nX3 0..1 arrays with every element unequal to 0, 1, 3, 5 or 6 king-move adjacent elements, with upper left element zero. 2
3, 9, 13, 30, 66, 123, 252, 535, 1074, 2194, 4530, 9231, 18873, 38722, 79180, 161992, 331766, 678927, 1389398, 2844206, 5821252, 11914196, 24386446, 49913147, 102159115, 209097391, 427973147, 875956927, 1792880557, 3669604702 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 3 of A304669.

LINKS

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

FORMULA

Empirical: a(n) = a(n-1) +4*a(n-3) +2*a(n-5) -a(n-7) -2*a(n-9) -2*a(n-11) -a(n-12)

EXAMPLE

Some solutions for n=5

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

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

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

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

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

CROSSREFS

Cf. A304669.

Sequence in context: A304350 A305913 A215443 * A068885 A305644 A316920

Adjacent sequences:  A304661 A304662 A304663 * A304665 A304666 A304667

KEYWORD

nonn

AUTHOR

R. H. Hardin, May 16 2018

STATUS

approved

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Last modified January 22 19:16 EST 2020. Contains 331153 sequences. (Running on oeis4.)