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A253403
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Number of (n+1)X(4+1) 0..2 arrays with every 2X2 subblock diagonal maximum plus antidiagonal minimum unequal to its neighbors horizontally, vertically and ne+sw antidiagonally
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1
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17560, 37828, 108950, 403698, 1739014, 7437150, 27085902, 115826070, 489226254, 1807771102, 7774449228, 32691341010, 120990997286, 520891540644, 2184829830574, 8087677107470, 34850307980588, 145865794236954
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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) = 160*a(n-3) -7952*a(n-6) +98358*a(n-9) +1917280*a(n-12) -53187384*a(n-15) -68774113*a(n-18) +7983927856*a(n-21) -4682894632*a(n-24) -687025828328*a(n-27) -4013350970720*a(n-30) -4983960145280*a(n-33) +22542564452080*a(n-36) +57373712662592*a(n-39) -74581831759040*a(n-42) -225211762413056*a(n-45) +204280702855424*a(n-48) +329790587612160*a(n-51) -337058300150784*a(n-54) -25034074472448*a(n-57) -449521975296*a(n-60) for n>69
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EXAMPLE
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Some solutions for n=3
..2..1..2..0..1....2..2..0..1..0....0..1..2..2..2....0..0..0..2..2
..2..0..0..1..2....2..1..0..0..1....0..0..0..2..1....0..1..0..2..0
..0..1..0..1..0....2..2..1..2..2....1..2..0..1..1....1..1..1..2..1
..0..1..2..2..0....2..2..0..0..1....2..1..0..0..0....2..2..0..1..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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