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A278152
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Number of nX3 0..1 arrays with every element both equal and not equal to some elements at offset (-1,-1) (-1,0) (-1,1) (0,-1) (0,1) (1,-1) or (1,0), with upper left element zero.
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1
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0, 7, 42, 268, 1759, 11675, 77102, 509336, 3365082, 22232537, 146885095, 970436014, 6411449580, 42358984701, 279856142429, 1848945655959, 12215561936959, 80705429566515, 533202352449825, 3522746241343707, 23273980363926953
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OFFSET
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1,2
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COMMENTS
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LINKS
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FORMULA
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Empirical: a(n) = 6*a(n-1) +5*a(n-2) -5*a(n-3) -4*a(n-4) -38*a(n-5) -25*a(n-6) +26*a(n-7) +3*a(n-8) +14*a(n-9) +19*a(n-10) -3*a(n-11) +3*a(n-12) -a(n-13) -a(n-14) for n>15
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EXAMPLE
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Some solutions for n=4
..0..1..0. .0..0..1. .0..0..1. .0..1..1. .0..1..1. .0..0..0. .0..0..1
..0..1..0. .1..1..0. .1..1..1. .0..1..0. .0..1..0. .1..1..0. .1..1..0
..1..1..0. .1..0..1. .0..0..1. .0..0..1. .1..0..1. .1..0..1. .0..1..0
..0..0..1. .0..0..1. .0..1..0. .0..1..1. .1..0..1. .1..1..1. .0..0..1
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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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