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A305240 Number of nX3 0..1 arrays with every element unequal to 0, 1, 2, 4 or 8 king-move adjacent elements, with upper left element zero. 1
4, 12, 18, 32, 86, 158, 343, 721, 1520, 3228, 6773, 14334, 30273, 63871, 134918, 284843, 601453, 1270011, 2681563, 5662260, 11955917, 25245070, 53305555, 112555500, 237663066, 501829940, 1059622929, 2237413464, 4724339318 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 3 of A305245.

LINKS

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

FORMULA

Empirical: a(n) = a(n-1) +2*a(n-2) +2*a(n-3) -a(n-4) -2*a(n-5) -3*a(n-6) -a(n-7) +a(n-8) for n>11

EXAMPLE

Some solutions for n=5

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

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

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

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

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

CROSSREFS

Cf. A305245.

Sequence in context: A301251 A062859 A300745 * A301106 A008237 A008120

Adjacent sequences:  A305237 A305238 A305239 * A305241 A305242 A305243

KEYWORD

nonn

AUTHOR

R. H. Hardin, May 28 2018

STATUS

approved

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Last modified November 27 03:56 EST 2021. Contains 349345 sequences. (Running on oeis4.)