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A232511
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Number of (n+1)X(4+1) 0..2 arrays with every element next to itself plus and minus one within the range 0..2 horizontally, diagonally or antidiagonally, with no adjacent elements equal
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1
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54, 326, 2516, 19138, 145682, 1110752, 8470018, 64594290, 492627324, 3757052022, 28653492802, 218528696816, 1666631440922, 12710736921242, 96939753662116, 739321100203858, 5638509196177426, 43002676390969828, 327964380966543498
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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) = 8*a(n-1) +a(n-2) -23*a(n-3) -48*a(n-4) -9*a(n-5) +40*a(n-6) +44*a(n-7) +5*a(n-8) -20*a(n-9) +3*a(n-10) +9*a(n-11) +6*a(n-12) -a(n-13) -2*a(n-14)
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EXAMPLE
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Some solutions for n=5
..2..1..0..1..0....2..1..0..1..2....0..1..2..1..0....0..1..0..1..0
..0..1..2..1..0....0..1..0..1..0....2..1..2..1..2....0..1..2..1..0
..2..1..2..1..0....0..1..0..1..2....0..1..2..1..0....0..1..2..1..2
..2..1..0..1..0....0..1..2..1..0....0..1..2..1..0....2..1..2..1..2
..2..1..0..1..0....2..1..0..1..2....2..1..2..1..0....0..1..0..1..0
..0..1..0..1..2....0..1..0..1..2....0..1..0..1..0....0..1..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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