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A281468
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Number of nX7 0..1 arrays with no element equal to more than two of its horizontal, diagonal or antidiagonal neighbors and with new values introduced in order 0 sequentially upwards.
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1
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64, 361, 145, 260, 472, 924, 1887, 3681, 7126, 14363, 29371, 59830, 122230, 250638, 513616, 1053242, 2163243, 4442634, 9122210, 18740008, 38502723, 79097291, 162508103, 333905314, 686048845, 1409580474, 2896272475, 5950951790
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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) = 2*a(n-1) +3*a(n-3) -4*a(n-4) -4*a(n-5) +a(n-7) +2*a(n-8) -a(n-9) +5*a(n-10) -3*a(n-12) for n>19
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EXAMPLE
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Some solutions for n=4
..0..1..0..0..1..0..1. .0..1..0..1..0..0..1. .0..0..1..0..1..0..0
..0..1..0..1..1..0..1. .1..1..0..1..0..1..1. .1..1..0..1..0..1..1
..0..1..0..1..0..0..1. .1..0..0..1..0..1..0. .0..1..0..1..0..1..0
..0..1..0..1..0..1..1. .1..0..1..1..0..1..0. .1..1..0..1..0..1..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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