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A281606
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Number of 3Xn 0..2 arrays with no element equal to more than one 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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5, 50, 209, 1283, 8180, 49572, 302304, 1849212, 11295326, 69003066, 421598546, 2575763454, 15736620000, 96143466614, 587391366384, 3588683849428, 21925168436114, 133952450888038, 818386359248384, 4999955088202190
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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) = 6*a(n-1) -4*a(n-2) +29*a(n-3) -15*a(n-4) +73*a(n-5) +11*a(n-6) -32*a(n-7) +6*a(n-8) +a(n-9) -30*a(n-10) -26*a(n-11) +10*a(n-12) +8*a(n-13) for n>15
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EXAMPLE
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Some solutions for n=4
..0..1..0..1. .0..1..0..1. .0..1..0..2. .0..1..2..1. .0..1..1..0
..2..1..2..1. .0..1..2..1. .0..2..0..2. .1..2..0..1. .2..0..2..2
..2..0..2..0. .2..1..0..0. .1..2..0..1. .0..2..0..2. .2..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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