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A253873
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Number of (3+2)X(n+2) 0..1 arrays with every 3X3 subblock diagonal maximum minus antidiagonal minimum nondecreasing horizontally, vertically and ne-to-sw antidiagonally
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1
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20480, 296960, 3939840, 52394496, 677982208, 8846579968, 114921882112, 1496191085824, 19441717373440, 252846568955136, 3286484917438976, 42729128633556224, 555429407389911552, 7220617056896949504
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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) = 17*a(n-1) -11*a(n-2) -693*a(n-3) +3244*a(n-4) -19932*a(n-5) +46560*a(n-6) +261248*a(n-7) -776832*a(n-8) +664576*a(n-9) -1263616*a(n-10) -15355904*a(n-11) +39215104*a(n-12) +46170112*a(n-13) -132120576*a(n-14) +1835008*a(n-15) +86507520*a(n-16) -117440512*a(n-17) +176160768*a(n-18) +16777216*a(n-19) -167772160*a(n-20) +67108864*a(n-21)
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EXAMPLE
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Some solutions for n=1
..1..0..1....1..0..1....0..1..0....0..1..1....0..1..1....0..1..1....1..1..1
..1..1..1....0..0..0....1..1..0....1..0..0....0..0..0....1..0..1....1..1..0
..1..1..1....1..0..0....1..1..0....1..1..0....1..1..0....1..0..0....1..0..1
..1..0..1....1..1..1....1..0..0....0..1..0....0..0..1....0..1..1....1..0..0
..0..0..0....1..0..0....1..0..1....0..0..1....1..1..0....1..0..1....1..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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