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A268890 Number of 5Xn binary arrays with some element plus some horizontally or antidiagonally adjacent neighbor totalling two exactly once. 1
0, 235, 2418, 31956, 317966, 3283890, 31427480, 299524050, 2777161184, 25505113994, 231143340184, 2077724593805, 18526267129268, 164165431218906, 1446558738555296, 12686251671077220, 110791183092125102 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Row 5 of A268886.

LINKS

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

FORMULA

Empirical: a(n) = 2*a(n-1) +97*a(n-2) +116*a(n-3) -2923*a(n-4) -10986*a(n-5) +4951*a(n-6) +72992*a(n-7) +36740*a(n-8) -223968*a(n-9) -159382*a(n-10) +423052*a(n-11) +256370*a(n-12) -539504*a(n-13) -176570*a(n-14) +450908*a(n-15) +6166*a(n-16) -217920*a(n-17) +57416*a(n-18) +45120*a(n-19) -25021*a(n-20) +562*a(n-21) +2089*a(n-22) -388*a(n-23) -31*a(n-24) +14*a(n-25) -a(n-26)

EXAMPLE

Some solutions for n=4

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

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

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

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

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

CROSSREFS

Cf. A268886.

Sequence in context: A129857 A146092 A257310 * A254676 A146126 A264325

Adjacent sequences:  A268887 A268888 A268889 * A268891 A268892 A268893

KEYWORD

nonn

AUTHOR

R. H. Hardin, Feb 15 2016

STATUS

approved

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Last modified July 27 15:47 EDT 2021. Contains 346307 sequences. (Running on oeis4.)