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A283721 Number of nX3 0..1 arrays with no 1 equal to more than two of its horizontal, diagonal and antidiagonal neighbors, with the exception of exactly one element. 1
0, 10, 159, 1304, 9819, 69972, 478164, 3182364, 20764075, 133429620, 847160264, 5326384974, 33218865533, 205768886352, 1267218413380, 7765068162382, 47373987672324, 287914794741192, 1743841385348260, 10529990498553708 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Column 3 of A283726.

LINKS

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

FORMULA

Empirical: a(n) = 10*a(n-1) -21*a(n-2) +8*a(n-3) -162*a(n-4) +38*a(n-5) -270*a(n-6) +654*a(n-7) +231*a(n-8) +1484*a(n-9) -390*a(n-10) -508*a(n-11) -2885*a(n-12) -2464*a(n-13) -316*a(n-14) +1760*a(n-15) +4524*a(n-16) +1888*a(n-17) -96*a(n-18) -1920*a(n-19) -1600*a(n-20)

EXAMPLE

Some solutions for n=4

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

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

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

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

CROSSREFS

Cf. A283726.

Sequence in context: A129460 A200989 A268883 * A239761 A245916 A245914

Adjacent sequences:  A283718 A283719 A283720 * A283722 A283723 A283724

KEYWORD

nonn

AUTHOR

R. H. Hardin, Mar 15 2017

STATUS

approved

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Last modified October 26 08:00 EDT 2021. Contains 348267 sequences. (Running on oeis4.)