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A253003
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Number of nX7 nonnegative integer arrays with upper left 0 and lower right its king-move distance away minus 3 and every value within 3 of its king move distance from the upper left and every value increasing by 0 or 1 with every step right, diagonally se or down
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1
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20, 140, 1028, 7235, 39758, 122833, 122833, 4915726, 59154789, 329035981, 1124010769, 2853903059, 5973571711, 10950733467, 18255251895, 28357151187, 41726455535, 58833189131, 80147376167, 106139040835, 137278207327
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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) = (235012096/3)*n^3 - 2126491008*n^2 + (58625640404/3)*n - 60801081325 for n>12
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EXAMPLE
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Some solutions for n=6
..0..1..1..1..1..2..3....0..0..1..1..1..2..3....0..1..1..1..2..3..3
..1..1..1..1..2..2..3....0..0..1..1..2..2..3....0..1..2..2..2..3..3
..1..1..1..1..2..2..3....0..1..1..1..2..2..3....1..1..2..2..2..3..3
..1..1..2..2..2..3..3....0..1..1..2..2..3..3....1..1..2..2..3..3..3
..1..2..2..2..3..3..3....1..1..1..2..3..3..3....2..2..2..3..3..3..3
..2..2..2..3..3..3..3....2..2..2..2..3..3..3....2..2..3..3..3..3..3
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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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