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A304474 Number of nX3 0..1 arrays with every element unequal to 0, 1, 2, 4 or 6 king-move adjacent elements, with upper left element zero. 1
4, 12, 19, 37, 94, 202, 428, 965, 2134, 4692, 10385, 22939, 50685, 112126, 247801, 547629, 1210890, 2677120, 5917928, 13083023, 28924080, 63944514, 141366373, 312528443, 690930487, 1527496422, 3376954419, 7465688699, 16504985560 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 3 of A304479.

LINKS

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

FORMULA

Empirical: a(n) = a(n-2) +6*a(n-3) +8*a(n-4) +5*a(n-5) -6*a(n-6) -22*a(n-7) -25*a(n-8) -14*a(n-9) +2*a(n-10) +7*a(n-11) +3*a(n-12) for n>13

EXAMPLE

Some solutions for n=5

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

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

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

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

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

CROSSREFS

Cf. A304479.

Sequence in context: A301184 A008177 A301230 * A301068 A169583 A239727

Adjacent sequences:  A304471 A304472 A304473 * A304475 A304476 A304477

KEYWORD

nonn

AUTHOR

R. H. Hardin, May 13 2018

STATUS

approved

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Last modified October 19 22:05 EDT 2021. Contains 348095 sequences. (Running on oeis4.)