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A320367
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Number of nX4 0..1 arrays with every element unequal to 0, 1, 2, 3 or 4 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero.
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1
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8, 128, 1612, 19840, 245060, 3027408, 37398884, 462004160, 5707334644, 70505149536, 870980328164, 10759593299088, 132917867720276, 1641991390503824, 20284223429413892, 250579706152958368
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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) = 16*a(n-1) -50*a(n-2) +68*a(n-3) -85*a(n-4) +12*a(n-5) -36*a(n-6) -12*a(n-7) +12*a(n-8) +16*a(n-9)
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EXAMPLE
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Some solutions for n=5
..0..0..0..0. .0..0..0..0. .0..0..0..0. .0..0..1..1. .0..0..0..0
..1..0..1..1. .1..1..1..0. .1..1..0..1. .0..0..1..0. .1..0..0..1
..1..0..1..0. .0..1..1..1. .1..0..1..1. .0..1..1..0. .1..0..0..0
..0..0..0..0. .0..0..1..0. .0..0..1..0. .1..1..0..1. .0..0..0..0
..1..1..0..1. .0..0..0..1. .0..0..1..0. .1..1..0..1. .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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