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A196805
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Number of nX4 0..4 arrays with each element x equal to the number its horizontal and vertical neighbors equal to 4,2,3,0,1 for x=0,1,2,3,4
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1
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1, 7, 37, 193, 1515, 8719, 52291, 334317, 2067173, 12663609, 78727511, 488078559, 3014804713, 18665197193, 115593457951, 715253390987, 4426801402571, 27403189146691, 169608418907807, 1049766166947791, 6497692031157569
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OFFSET
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1,2
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COMMENTS
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Every 0 is next to 0 4's, every 1 is next to 1 2's, every 2 is next to 2 3's, every 3 is next to 3 0's, every 4 is next to 4 1's
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LINKS
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FORMULA
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Empirical: a(n) = 2*a(n-1) +9*a(n-2) +82*a(n-3) +137*a(n-4) +25*a(n-5) -6*a(n-6) +79*a(n-7) -153*a(n-8) -112*a(n-9) +76*a(n-10) -160*a(n-11) +136*a(n-12) -24*a(n-13)
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EXAMPLE
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Some solutions for n=5
..0..0..3..0....0..0..3..0....0..0..0..0....0..3..0..0....0..0..0..0
..0..3..0..3....0..0..0..0....0..1..0..0....0..0..3..0....3..0..0..0
..0..2..0..0....0..0..0..3....1..2..3..0....0..3..2..0....0..3..3..0
..0..3..0..0....3..0..0..0....0..3..0..3....0..0..0..3....3..0..0..3
..0..0..0..0....0..3..0..0....0..0..0..0....0..0..0..0....0..0..3..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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