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A269014 Number of 4 X n binary arrays with some element plus some horizontally, diagonally or antidiagonally adjacent neighbor totalling two exactly once. 1
0, 48, 224, 2136, 10976, 73568, 390064, 2291728, 12190944, 67387784, 356115520, 1906181472, 9983123936, 52432319344, 272227610848, 1412208727736, 7276913394080, 37421599567712, 191604936958480, 978880041945808 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

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.: 8*x^2*(6 + 4*x - 13*x^2 - 12*x^3) / (1 - 2*x - 16*x^2 + 7*x^3 + 18*x^4)^2. - Colin Barker, Jan 18 2019

EXAMPLE

Some solutions for n=4:

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

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

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

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

CROSSREFS

Row 4 of A269011.

Sequence in context: A062248 A100146 A235542 * A265422 A211729 A211738

Adjacent sequences:  A269011 A269012 A269013 * A269015 A269016 A269017

KEYWORD

nonn

AUTHOR

R. H. Hardin, Feb 17 2016

STATUS

approved

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Last modified September 26 14:42 EDT 2021. Contains 347668 sequences. (Running on oeis4.)