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A275231
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Number of 6 X n 0..2 arrays with no element equal to any value at offset (-2,-1) (-2,1) or (-1,0) and new values introduced in order 0..2.
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1
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16, 162, 2282, 32388, 460034, 6534900, 92831330, 1318716132, 18733040162, 266112481908, 3780264894914, 53700610406820, 762844837516610, 10836603937486452, 153939541994209442, 2186790504309773028
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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) = 19*a(n-1) - 75*a(n-2) + 101*a(n-3) - 44*a(n-4) for n>5.
Empirical g.f.: 2*x*(8 - 71*x + 202*x^2 - 218*x^3 + 77*x^4) / ((1 - x)*(1 - 18*x + 57*x^2 - 44*x^3)). - Colin Barker, Feb 02 2019
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EXAMPLE
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Some solutions for n=4:
..0..0..1..2. .0..1..2..2. .0..1..0..1. .0..1..2..1. .0..1..2..1
..2..1..2..1. .1..0..1..0. .2..0..1..0. .1..2..1..0. .2..2..1..2
..1..2..1..2. .2..1..0..1. .0..2..0..2. .0..1..0..1. .0..1..2..0
..2..1..0..1. .1..0..1..0. .1..0..2..0. .1..0..1..0. .1..0..1..2
..1..2..1..0. .0..1..2..2. .0..1..1..1. .0..1..2..1. .0..1..2..1
..2..1..2..1. .1..2..1..0. .1..0..2..0. .1..0..1..2. .2..2..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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