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A237931
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Number of (n+1)X(1+1) 0..3 arrays with the upper median plus the lower median minus the minimum of every 2X2 subblock differing from its horizontal and vertical neighbors by exactly one
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1
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256, 1718, 11701, 81402, 563166, 3880918, 26804881, 185489824, 1282099556, 8852862392, 61169759404, 422870170848, 2922385929712, 20190059774152, 139517455447976, 964213093638072, 6663225933024004, 46041769193957056
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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) = 1888*a(n-4) +26908*a(n-6) -301104*a(n-8) -4523964*a(n-10) +9356144*a(n-12) +158092496*a(n-14) +15024960*a(n-16) -2150807552*a(n-18) -1973442560*a(n-20) +11283515392*a(n-22) +13873016832*a(n-24) -19456245760*a(n-26) -21131821056*a(n-28) +10415243264*a(n-30) +385875968*a(n-32) -96468992*a(n-34) -16777216*a(n-36)
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EXAMPLE
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Some solutions for n=4
..1..0....2..2....0..3....2..2....2..1....2..1....1..0....0..2....1..1....0..2
..1..3....3..3....1..2....2..1....0..1....1..0....0..2....3..2....0..1....0..2
..2..2....2..1....3..1....2..1....2..2....0..1....1..1....0..3....2..2....3..1
..3..0....2..2....3..1....3..0....2..3....1..2....1..3....1..3....0..2....2..3
..3..2....2..0....1..2....3..1....3..2....3..2....1..2....1..3....3..1....0..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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