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A269017 Number of 7Xn binary arrays with some element plus some horizontally, diagonally or antidiagonally adjacent neighbor totalling two exactly once. 1
0, 1183, 22654, 566656, 10002542, 192100836, 3258530608, 56916559941, 940858829922, 15693717431672, 254647316356204, 4136953520012344, 66194476183413344, 1057401264518371179, 16737766253590304358 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Row 7 of A269011.

LINKS

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

FORMULA

Empirical: a(n) = 18*a(n-1) +287*a(n-2) -5714*a(n-3) -26548*a(n-4) +662854*a(n-5) +503265*a(n-6) -36588730*a(n-7) +43719737*a(n-8) +1055812740*a(n-9) -2531478280*a(n-10) -16536573196*a(n-11) +55382641489*a(n-12) +144894098686*a(n-13) -653413097167*a(n-14) -674041638674*a(n-15) +4637903423724*a(n-16) +1002070742726*a(n-17) -20672353979137*a(n-18) +5547728650154*a(n-19) +58313438730423*a(n-20) -34583201988384*a(n-21) -101896578743152*a(n-22) +86334749395584*a(n-23) +103754510061648*a(n-24) -115277187600000*a(n-25) -52616533613760*a(n-26) +83474612042112*a(n-27) +5618980228032*a(n-28) -30037873821696*a(n-29) +4537384086528*a(n-30) +4167543840768*a(n-31) -1173876903936*a(n-32)

EXAMPLE

Some solutions for n=3

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

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

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

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

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

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

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

CROSSREFS

Cf. A269011.

Sequence in context: A321867 A210847 A320716 * A328064 A280516 A205994

Adjacent sequences:  A269014 A269015 A269016 * A269018 A269019 A269020

KEYWORD

nonn

AUTHOR

R. H. Hardin, Feb 17 2016

STATUS

approved

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Last modified October 19 22:05 EDT 2021. Contains 348095 sequences. (Running on oeis4.)