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A317225
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Number of nX3 0..1 arrays with every element unequal to 0, 1, 2, 3, 6, 7 or 8 king-move adjacent elements, with upper left element zero.
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1
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4, 21, 46, 150, 488, 1468, 4626, 14720, 45811, 143798, 453581, 1423094, 4469903, 14063611, 44197158, 138899518, 436737933, 1372924949, 4315682539, 13567748610, 42653241731, 134086614407, 421533391249, 1325188322229, 4166003679092
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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) = 3*a(n-1) +a(n-2) +7*a(n-3) -22*a(n-4) -23*a(n-5) +8*a(n-6) +29*a(n-7) +22*a(n-8) -20*a(n-9) -10*a(n-10) for n>12
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EXAMPLE
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Some solutions for n=5
..0..1..1. .0..0..1. .0..0..1. .0..0..0. .0..1..1. .0..0..1. .0..0..1
..1..1..1. .0..0..0. .0..1..0. .0..1..1. .0..1..1. .0..0..0. .1..0..1
..1..1..1. .0..1..0. .0..1..0. .0..1..0. .1..0..1. .0..1..0. .1..1..1
..1..0..1. .0..1..0. .0..0..0. .0..0..0. .1..1..1. .0..0..0. .1..0..0
..0..0..1. .0..0..0. .1..0..1. .1..0..1. .0..1..0. .1..0..0. .1..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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