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A274855
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Number of n X 5 0..2 arrays with no element equal to any value at offset (-1,0) (0,-1) or (-2,-2) and new values introduced in order 0..2.
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1
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8, 81, 100, 330, 1085, 3602, 12102, 40901, 138307, 467309, 1578541, 5333233, 18021770, 60899601, 205786949, 695366607, 2349691060, 7939809084, 26829343060, 90658737265, 306343718596, 1035161871379, 3497901910024, 11819715442581
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OFFSET
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1,1
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LINKS
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FORMULA
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Empirical: a(n) = 8*a(n-1) - 27*a(n-2) + 56*a(n-3) - 75*a(n-4) + 61*a(n-5) - 28*a(n-6) + 7*a(n-7) - a(n-8) for n>10.
Empirical g.f.: x*(8 + 17*x - 332*x^2 + 1269*x^3 - 2791*x^4 + 3819*x^5 - 3116*x^6 + 1441*x^7 - 373*x^8 + 54*x^9) / ((1 - x)^3*(1 - 5*x + 9*x^2 - 13*x^3 + 4*x^4 - x^5)). - Colin Barker, Jan 31 2019
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EXAMPLE
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Some solutions for n=4:
..0..1..0..1..2. .0..1..2..0..2. .0..1..2..1..2. .0..1..2..0..2
..1..0..1..2..0. .2..0..1..2..0. .1..2..1..2..0. .2..0..1..2..0
..0..1..2..0..2. .0..1..2..0..1. .2..0..2..0..1. .0..1..2..0..1
..1..2..0..2..0. .1..2..1..2..0. .0..2..0..1..0. .2..0..1..2..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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