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A220808
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Equals one maps: number of nX4 binary arrays indicating the locations of corresponding elements equal to exactly one of their horizontal, vertical and antidiagonal neighbors in a random 0..2 nX4 array
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1
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8, 168, 3466, 62400, 1037774, 16734366, 268264812, 4294285044, 68716748256, 1099500713960, 17592142389240, 281474802089984, 4503598928887808, 72057591243997184, 1152921493431123968, 18446744029006659584
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OFFSET
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1,1
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COMMENTS
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LINKS
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FORMULA
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Empirical: a(n) = 20*a(n-1) -64*a(n-2) for n>13
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EXAMPLE
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Some solutions for n=3
..0..1..0..0....0..0..1..1....0..0..1..1....0..1..1..0....1..0..1..1
..1..0..0..1....1..1..0..1....1..1..0..1....1..0..0..1....0..0..1..0
..0..0..0..0....0..0..0..0....0..0..1..0....1..1..0..0....0..0..0..0
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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