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A320397 Number of nX3 0..1 arrays with every element unequal to 0, 1, 2, 3 or 5 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero. 1
4, 28, 142, 732, 3694, 18754, 94842, 480321, 2431390, 12309913, 62320210, 315508545, 1597316261, 8086701105, 40940363689, 207267894413, 1049330682760, 5312423710470, 26895092511498, 136161202337290, 689340370573277 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 3 of A320402.

LINKS

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

FORMULA

Empirical: a(n) = 3*a(n-1) +11*a(n-2) -a(n-3) -8*a(n-4) -a(n-5) -26*a(n-6) -5*a(n-7) +18*a(n-8) +5*a(n-9) -5*a(n-10) -4*a(n-11) -a(n-12) for n>14

EXAMPLE

Some solutions for n=5

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

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

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

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

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

CROSSREFS

Cf. A320402.

Sequence in context: A051536 A273565 A273558 * A273611 A043013 A145544

Adjacent sequences:  A320394 A320395 A320396 * A320398 A320399 A320400

KEYWORD

nonn

AUTHOR

R. H. Hardin, Oct 12 2018

STATUS

approved

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Last modified January 16 19:48 EST 2022. Contains 350376 sequences. (Running on oeis4.)