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A238148
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Number of (n+1)X(1+1) 0..3 arrays with the maximum plus the upper median of every 2X2 subblock differing from its horizontal and vertical neighbors by exactly one
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1
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256, 1608, 10664, 72584, 499560, 3342416, 22488016, 152285824, 1043035504, 6998475712, 47273279296, 319462663168, 2181201937664, 14658851660800, 99259562449664, 669930900621824, 4565506277964288, 30712312453320704
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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) = 1728*a(n-4) +17152*a(n-6) -2064*a(n-8) -513920*a(n-10) -1449280*a(n-12) -772864*a(n-14) +601600*a(n-16) +334848*a(n-18) -331776*a(n-20) for n>21
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EXAMPLE
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Some solutions for n=4
..0..2....1..1....1..0....3..2....0..3....0..1....2..1....0..3....2..3....2..0
..0..2....0..3....0..2....3..2....3..2....2..0....0..0....2..3....0..2....0..3
..1..3....2..0....2..1....2..2....0..2....0..2....2..0....0..1....2..1....2..3
..1..1....2..1....1..0....0..2....1..2....3..0....0..1....0..3....0..3....0..1
..2..1....0..0....3..0....3..0....1..1....0..1....3..1....2..1....3..2....3..1
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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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