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A253396
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Number of (n+1)X(7+1) 0..1 arrays with every 2X2 subblock antidiagonal maximum minus diagonal minimum nondecreasing horizontally and diagonal maximum minus antidiagonal minimum nondecreasing vertically
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1
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704, 391, 520, 823, 1269, 1855, 2726, 3810, 5311, 7163, 9569, 12493, 16140, 20493, 25773, 31978, 39346, 47891, 57867, 69304, 82472, 97417, 114425, 133558, 155118, 179183, 206071, 235876, 268932, 305349, 345477, 389442, 437610, 490123, 547363
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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) = 4*a(n-1) -5*a(n-2) +5*a(n-4) -4*a(n-5) +a(n-6) for n>18
Empirical for n mod 2 = 0: a(n) = (1/3)*n^4 - (1/3)*n^3 + (337/6)*n^2 - (1423/6)*n + 914 for n>12
Empirical for n mod 2 = 1: a(n) = (1/3)*n^4 - (1/3)*n^3 + (337/6)*n^2 - (1423/6)*n + 943 for n>12
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EXAMPLE
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Some solutions for n=4
..0..0..0..0..0..0..0..1....1..1..1..1..1..1..0..1....1..1..1..0..0..0..0..1
..0..0..0..0..0..0..1..0....1..1..1..1..1..1..0..0....1..1..1..1..1..1..1..1
..0..0..0..0..0..0..1..0....1..1..1..1..1..1..1..1....1..0..0..0..0..0..0..0
..0..0..0..0..0..0..1..0....1..1..1..1..1..0..0..0....1..1..1..1..1..1..1..1
..0..0..0..0..0..0..1..0....1..1..1..1..1..1..1..1....0..0..0..0..0..0..0..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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