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A303722 Number of nX3 0..1 arrays with every element unequal to 0, 1, 2 or 3 king-move adjacent elements, with upper left element zero. 1
4, 21, 23, 46, 77, 151, 294, 549, 1051, 2032, 3877, 7421, 14262, 27333, 52371, 100472, 192665, 369353, 708294, 1358233, 2604287, 4993776, 9575821, 18361581, 35208486, 67513133, 129457227, 248235688, 475996017, 912729185, 1750170310, 3355977073 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 3 of A303727.

LINKS

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

FORMULA

Empirical: a(n) = 2*a(n-1) +a(n-3) -2*a(n-4) -2*a(n-5) +2*a(n-6) for n>9

EXAMPLE

Some solutions for n=5

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

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

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

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

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

CROSSREFS

Cf. A303727.

Sequence in context: A329404 A076943 A138228 * A305225 A272954 A133784

Adjacent sequences:  A303719 A303720 A303721 * A303723 A303724 A303725

KEYWORD

nonn

AUTHOR

R. H. Hardin, Apr 29 2018

STATUS

approved

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Last modified October 3 18:24 EDT 2022. Contains 357237 sequences. (Running on oeis4.)