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A268771 Number of nX5 0..2 arrays with some element plus some horizontally, vertically, diagonally or antidiagonally adjacent neighbor totalling two exactly once. 1
96, 248, 1524, 10340, 64112, 387146, 2258084, 12951796, 73011192, 406925194, 2244513800, 12281806624, 66734787464, 360505595710, 1937557458852, 10367717536488, 55261185262316, 293537189567482, 1554428843176696 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 5 of A268774.

LINKS

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

FORMULA

Empirical: a(n) = 4*a(n-1) +28*a(n-2) -62*a(n-3) -314*a(n-4) +78*a(n-5) +867*a(n-6) +6*a(n-7) -859*a(n-8) +46*a(n-9) +215*a(n-10) -8*a(n-11) -16*a(n-12) for n>14

EXAMPLE

Some solutions for n=4

..1..2..1..2..2. .2..1..2..1..2. .0..0..1..1..0. .2..2..1..2..1

..2..2..2..2..2. .2..1..2..2..2. .0..0..0..0..0. .2..2..2..2..2

..1..2..2..2..1. .2..2..2..2..2. .0..1..0..1..0. .2..1..2..2..2

..2..2..2..2..1. .2..2..2..2..1. .0..0..0..0..0. .2..2..1..2..1

CROSSREFS

Cf. A268774.

Sequence in context: A125511 A124106 A304510 * A202898 A202891 A232939

Adjacent sequences: A268768 A268769 A268770 * A268772 A268773 A268774

KEYWORD

nonn

AUTHOR

R. H. Hardin, Feb 13 2016

STATUS

approved

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Last modified February 2 21:10 EST 2023. Contains 360024 sequences. (Running on oeis4.)