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A269078 Number of 4 X n binary arrays with some element plus some horizontally, diagonally or antidiagonally adjacent neighbor totalling two not more than once. 1
16, 89, 537, 3288, 17713, 102545, 542112, 2991561, 15699273, 84015848, 437869217, 2298582593, 11896438960, 61665786297, 317089210745, 1629210973432, 8329629544721, 42518834195697, 216316340106688, 1098583548812969 (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) = 4*a(n-1) + 28*a(n-2) - 78*a(n-3) - 264*a(n-4) + 296*a(n-5) + 527*a(n-6) - 252*a(n-7) - 324*a(n-8).

Empirical g.f.: x*(16 + 25*x - 267*x^2 - 104*x^3 + 691*x^4 + 275*x^5 - 576*x^6 - 324*x^7) / (1 - 2*x - 16*x^2 + 7*x^3 + 18*x^4)^2. - Colin Barker, Jan 19 2019

EXAMPLE

Some solutions for n=4:

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

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

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

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

CROSSREFS

Row 4 of A269075.

Sequence in context: A301888 A302084 A229399 * A240262 A264531 A192129

Adjacent sequences:  A269075 A269076 A269077 * A269079 A269080 A269081

KEYWORD

nonn

AUTHOR

R. H. Hardin, Feb 19 2016

STATUS

approved

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Last modified October 23 23:51 EDT 2019. Contains 328379 sequences. (Running on oeis4.)