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A268884 Number of nX6 binary arrays with some element plus some horizontally or antidiagonally adjacent neighbor totalling two exactly once. 1
20, 475, 9996, 186732, 3283890, 55491832, 911930096, 14681855846, 232688402028, 3642322709900, 56444213311842, 867475989937560, 13239446101273360, 200865483664370358, 3031934392327858732, 45561723449682618252 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 6 of A268886.

LINKS

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

FORMULA

Empirical: a(n) = 42*a(n-1) -665*a(n-2) +5138*a(n-3) -21972*a(n-4) +55274*a(n-5) -83769*a(n-6) +76202*a(n-7) -40273*a(n-8) +11304*a(n-9) -1296*a(n-10) for n>12

EXAMPLE

Some solutions for n=4

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

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

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

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

CROSSREFS

Cf. A268886.

Sequence in context: A049382 A288034 A272553 * A324069 A065412 A159753

Adjacent sequences:  A268881 A268882 A268883 * A268885 A268886 A268887

KEYWORD

nonn

AUTHOR

R. H. Hardin, Feb 15 2016

STATUS

approved

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Last modified December 5 08:36 EST 2021. Contains 349543 sequences. (Running on oeis4.)