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A253362
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Number of (n+2) X (3+2) 0..1 arrays with every 2 X 2 and 3 X 3 subblock diagonal maximum minus antidiagonal minimum unequal to its neighbors horizontally and vertically.
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1
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560, 960, 2992, 5280, 13800, 27072, 63496, 130464, 297288, 612480, 1410760, 2875104, 6716232, 13589568, 31922056, 64500000, 151450440, 306332928, 718070344, 1453854816, 3404870472, 6895922880, 16148448520, 32703297696
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OFFSET
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1,1
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LINKS
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FORMULA
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Empirical: a(n) = 7*a(n-2) - 15*a(n-4) + 17*a(n-6) + 16*a(n-8) for n>11.
Empirical g.f.: 8*x*(70 + 120*x - 116*x^2 - 180*x^3 + 157*x^4 + 564*x^5 + 282*x^6 + 480*x^7 - x^8 + 24*x^9 - 36*x^10) / (1 - 7*x^2 + 15*x^4 - 17*x^6 - 16*x^8). - Colin Barker, Dec 11 2018
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EXAMPLE
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Some solutions for n=4:
..0..0..0..0..0....1..0..0..0..0....1..0..0..0..1....0..1..0..1..0
..0..1..0..1..0....0..1..0..1..0....0..1..0..1..0....1..0..0..0..0
..1..0..1..0..0....1..0..0..0..0....1..0..0..0..0....0..1..0..1..0
..0..0..0..0..0....0..1..0..1..0....0..0..0..1..0....1..0..0..0..1
..1..0..1..0..1....0..0..0..0..0....1..0..1..0..1....0..1..0..1..0
..1..1..0..1..0....0..1..0..1..0....0..0..0..1..0....0..0..0..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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