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A320359 Number of nX3 0..1 arrays with every element unequal to 2, 3, 4 or 6 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero. 1
0, 1, 4, 13, 60, 258, 1111, 4836, 21007, 91214, 396170, 1720608, 7472694, 32454615, 140953263, 612172021, 2658715999, 11547033504, 50149763813, 217804756979, 945944877379, 4108320326435, 17842790116095, 77492779006291 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

COMMENTS

Column 3 of A320364.

LINKS

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

FORMULA

Empirical: a(n) = 5*a(n-1) -4*a(n-2) +9*a(n-3) -19*a(n-4) +12*a(n-5) -24*a(n-6) +5*a(n-7) -9*a(n-8) +28*a(n-9) +20*a(n-10) -13*a(n-11) -31*a(n-12) -8*a(n-13) +14*a(n-14) +19*a(n-15) +4*a(n-16) -a(n-17) -2*a(n-18) for n>20

EXAMPLE

Some solutions for n=5

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

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

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

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

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

CROSSREFS

Cf. A320364.

Sequence in context: A241470 A219367 A149487 * A057712 A208592 A213093

Adjacent sequences:  A320356 A320357 A320358 * A320360 A320361 A320362

KEYWORD

nonn

AUTHOR

R. H. Hardin, Oct 11 2018

STATUS

approved

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Last modified July 21 21:14 EDT 2019. Contains 325199 sequences. (Running on oeis4.)