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A283410 Number of n X 3 0..1 arrays with no 1 equal to more than three of its horizontal, vertical and antidiagonal neighbors. 1
8, 61, 416, 2944, 20744, 146228, 1030788, 7266120, 51219756, 361053936, 2545110952, 17940781184, 126466639652, 891477956620, 6284131129240, 44297566481868, 312258664857680, 2201147411081008, 15516142450416040 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

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

FORMULA

Empirical: a(n) = 5*a(n-1) + 13*a(n-2) + 10*a(n-3) + a(n-4) + 2*a(n-5) for n>7.

Empirical g.f.: x*(1 + x)*(8 + 13*x - 6*x^2 - 3*x^3 + x^4 - 2*x^5) / (1 - 5*x - 13*x^2 - 10*x^3 - x^4 - 2*x^5). - Colin Barker, Feb 21 2019

EXAMPLE

Some solutions for n=4:

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

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

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

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

CROSSREFS

Column 3 of A283415.

Sequence in context: A071401 A247535 A283852 * A081907 A278596 A190976

Adjacent sequences:  A283407 A283408 A283409 * A283411 A283412 A283413

KEYWORD

nonn

AUTHOR

R. H. Hardin, Mar 07 2017

STATUS

approved

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Last modified May 17 04:33 EDT 2022. Contains 353730 sequences. (Running on oeis4.)