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A283095 Number of nX3 0..1 arrays with no 1 equal to more than one of its horizontal and vertical neighbors, with the exception of exactly two elements. 1
0, 6, 72, 600, 4607, 31669, 208949, 1324269, 8152245, 49070731, 289979290, 1687730558, 9698213032, 55123714128, 310376329220, 1733254750248, 9609161226263, 52931141892017, 289892095063747, 1579473182908079 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Column 3 of A283100.

LINKS

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

FORMULA

Empirical: a(n) = 6*a(n-1) +18*a(n-2) -52*a(n-3) -381*a(n-4) -543*a(n-5) +1654*a(n-6) +8943*a(n-7) +19026*a(n-8) +20615*a(n-9) +3639*a(n-10) -22728*a(n-11) -33125*a(n-12) -16047*a(n-13) +8640*a(n-14) +16878*a(n-15) +9570*a(n-16) +336*a(n-17) -3439*a(n-18) -2340*a(n-19) -477*a(n-20) +210*a(n-21) +216*a(n-22) +51*a(n-23) -13*a(n-24) -6*a(n-25) -3*a(n-26) +a(n-27)

EXAMPLE

Some solutions for n=4

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

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

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

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

CROSSREFS

Cf. A283100.

Sequence in context: A129532 A151719 A118313 * A281774 A036292 A061690

Adjacent sequences:  A283092 A283093 A283094 * A283096 A283097 A283098

KEYWORD

nonn

AUTHOR

R. H. Hardin, Feb 28 2017

STATUS

approved

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Last modified April 3 04:21 EDT 2020. Contains 333195 sequences. (Running on oeis4.)