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A269016 Number of 6Xn binary arrays with some element plus some horizontally, diagonally or antidiagonally adjacent neighbor totalling two exactly once. 1
0, 420, 4952, 91048, 1053432, 14382480, 164351184, 2008761644, 22653710120, 262438771480, 2922424553104, 32858512559296, 361841100434016, 3993863461953940, 43568235211010040, 474957563309125640 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Row 6 of A269011.

LINKS

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

FORMULA

Empirical: a(n) = 8*a(n-1) +160*a(n-2) -980*a(n-3) -9416*a(n-4) +38056*a(n-5) +226410*a(n-6) -670648*a(n-7) -2592568*a(n-8) +5911340*a(n-9) +15294568*a(n-10) -26316136*a(n-11) -50480497*a(n-12) +59619248*a(n-13) +94091288*a(n-14) -64298400*a(n-15) -91176864*a(n-16) +26645760*a(n-17) +36563904*a(n-18) -3642624*a(n-19) -4981824*a(n-20)

EXAMPLE

Some solutions for n=4

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

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

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

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

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

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

CROSSREFS

Cf. A269011.

Sequence in context: A160372 A171259 A061125 * A317983 A179718 A166784

Adjacent sequences:  A269013 A269014 A269015 * A269017 A269018 A269019

KEYWORD

nonn

AUTHOR

R. H. Hardin, Feb 17 2016

STATUS

approved

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Last modified October 24 18:08 EDT 2021. Contains 348233 sequences. (Running on oeis4.)