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A305511 Number of nX3 0..1 arrays with every element unequal to 1, 2, 5, 6 or 8 king-move adjacent elements, with upper left element zero. 1
1, 2, 5, 6, 8, 19, 33, 60, 107, 204, 375, 677, 1253, 2329, 4252, 7824, 14454, 26591, 48908, 90088, 165947, 305495, 562342, 1035675, 1907146, 3511035, 6465055, 11904935, 21919763, 40360338, 74316988, 136840634, 251963379, 463940762 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Column 3 of A305516.

LINKS

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

FORMULA

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

EXAMPLE

Some solutions for n=5

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

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

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

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

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

CROSSREFS

Cf. A305516.

Sequence in context: A326854 A097685 A136369 * A269472 A244272 A007573

Adjacent sequences:  A305508 A305509 A305510 * A305512 A305513 A305514

KEYWORD

nonn

AUTHOR

R. H. Hardin, Jun 03 2018

STATUS

approved

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Last modified October 1 00:54 EDT 2020. Contains 337440 sequences. (Running on oeis4.)