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A283197 Number of n X 2 0..1 arrays with no 1 equal to more than two of its horizontal and vertical neighbors, with the exception of exactly one element. 2
0, 0, 6, 36, 176, 824, 3668, 15808, 66640, 276184, 1129482, 4570084, 18329920, 72981648, 288779688, 1136580576, 4452663936, 17372989712, 67541322638, 261743811012, 1011439313456, 3898369209992, 14990343112316, 57519762677984 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

COMMENTS

Column 2 of A283203.

LINKS

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

FORMULA

Empirical: a(n) = 6*a(n-1) - 5*a(n-2) - 8*a(n-3) - 18*a(n-4) - 4*a(n-5) + 6*a(n-6) + 8*a(n-7) + 3*a(n-8) - 2*a(n-9) - a(n-10).

Empirical g.f.: 2*x^3*(1 + x)*(3 - 3*x - 2*x^2) / (1 - 3*x - 2*x^2 - 2*x^3 + x^4 + x^5)^2. - Colin Barker, Mar 22 2018

EXAMPLE

Some solutions for n=4:

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

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

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

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

CROSSREFS

Cf. A283203.

Sequence in context: A132165 A200573 A224130 * A218265 A258629 A294465

Adjacent sequences:  A283194 A283195 A283196 * A283198 A283199 A283200

KEYWORD

nonn

AUTHOR

R. H. Hardin, Mar 02 2017

STATUS

approved

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Last modified October 18 08:58 EDT 2021. Contains 348067 sequences. (Running on oeis4.)