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A317120
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Number of nX3 0..1 arrays with every element unequal to 0, 1, 2, 3, 5, 7 or 8 king-move adjacent elements, with upper left element zero.
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1
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4, 23, 82, 302, 1164, 4561, 17966, 70913, 280153, 1107258, 4377083, 17304434, 68414244, 270485001, 1069407613, 4228096809, 16716574533, 66092165685, 261308072698, 1033131823544, 4084686061176, 16149595233372, 63850544759048
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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) = 4*a(n-1) +2*a(n-2) -4*a(n-3) -19*a(n-4) -3*a(n-5) +20*a(n-6) +11*a(n-7) -8*a(n-8) +19*a(n-9) +19*a(n-10) -10*a(n-11) -21*a(n-12) -9*a(n-13) +2*a(n-14) -14*a(n-15) -8*a(n-16)
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EXAMPLE
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Some solutions for n=5
..0..0..1. .0..1..1. .0..1..0. .0..0..1. .0..0..0. .0..1..0. .0..0..1
..1..0..0. .1..0..1. .0..0..0. .0..0..1. .1..1..0. .0..1..1. .0..0..0
..0..0..0. .1..1..1. .1..0..0. .1..1..1. .1..1..0. .1..0..0. .1..1..0
..0..0..0. .1..1..1. .0..0..1. .1..1..0. .1..1..0. .1..1..0. .0..1..1
..0..0..1. .0..0..0. .1..0..0. .1..1..1. .0..0..0. .0..0..1. .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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