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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
OFFSET
1,1
COMMENTS
Column 5 of A268774.
LINKS
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
KEYWORD
nonn
AUTHOR
R. H. Hardin, Feb 13 2016
STATUS
approved