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A268746
Number of nX4 binary arrays with some element plus some horizontally or vertically adjacent neighbor totalling two no more than once.
1
13, 89, 623, 4110, 26334, 165019, 1016807, 6183665, 37209717, 221970102, 1314544140, 7737069617, 45297553803, 263980824665, 1532201345489, 8861529601362, 51088246525260, 293694819166095, 1684057081243885
OFFSET
1,1
COMMENTS
Column 4 of A268750.
LINKS
FORMULA
Empirical: a(n) = 8*a(n-1) +2*a(n-2) -82*a(n-3) -49*a(n-4) +124*a(n-5) +39*a(n-6) -58*a(n-7) -6*a(n-8) +8*a(n-9) -a(n-10)
EXAMPLE
Some solutions for n=4
..0..1..0..0. .0..0..0..0. .0..0..0..0. .0..0..0..1. .0..1..0..1
..0..0..0..1. .1..0..0..0. .1..0..0..1. .0..0..0..0. .1..0..1..0
..1..0..0..0. .0..0..1..0. .0..1..0..0. .1..0..0..0. .0..0..0..0
..1..0..0..1. .1..0..1..0. .1..0..1..0. .0..0..0..0. .0..0..1..0
CROSSREFS
Cf. A268750.
Sequence in context: A357219 A082099 A282858 * A152867 A026912 A161465
KEYWORD
nonn
AUTHOR
R. H. Hardin, Feb 12 2016
STATUS
approved