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A237561
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Number of (n+1)X(2+1) 0..2 arrays with the upper median plus the lower median of every 2X2 subblock differing from its horizontal and vertical neighbors by exactly one
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1
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316, 1536, 7356, 36168, 175768, 848720, 4121060, 20050460, 97225972, 471641072, 2290359200, 11118632740, 53953373220, 261887194692, 1271260706180, 6170274480252, 29948363314372, 145366959304036, 705586332210288
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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) = 2*a(n-2) +42*a(n-3) +208*a(n-4) +293*a(n-5) +900*a(n-6) -12*a(n-7) -857*a(n-8) -1583*a(n-9) -4726*a(n-10) +4946*a(n-11) +5993*a(n-12) +3312*a(n-13) +3822*a(n-14) -3319*a(n-15) -540*a(n-16) -32*a(n-17)
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EXAMPLE
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Some solutions for n=5
..0..1..0....0..2..0....0..0..1....0..1..1....0..1..0....0..2..0....1..2..1
..0..1..2....0..1..1....1..2..1....1..0..1....2..2..1....2..0..1....1..1..2
..2..1..2....0..0..0....1..1..2....0..0..1....2..0..2....1..0..0....2..2..2
..1..2..2....1..1..0....0..0..1....1..1..2....1..2..0....2..1..1....0..0..1
..0..1..1....0..1..0....1..0..2....1..2..0....1..0..1....2..1..2....1..1..2
..0..2..0....0..2..1....1..0..0....2..0..2....0..2..1....0..1..2....0..2..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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