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A223841
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Number of 5Xn 0..1 arrays with rows and antidiagonals unimodal and columns nondecreasing
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1
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6, 36, 149, 471, 1240, 2884, 6159, 12371, 23716, 43790, 78342, 136368, 231677, 385101, 627571, 1004341, 1580713, 2449699, 3742152, 5640008, 8393406, 12342594, 17945687, 25813519, 36753026, 51820812, 72388786, 100224016, 137585227
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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) = (1/3628800)*n^10 - (1/241920)*n^9 + (17/120960)*n^8 - (1/13440)*n^7 + (3733/172800)*n^6 - (893/11520)*n^5 + (178931/90720)*n^4 - (188123/60480)*n^3 + (504149/25200)*n^2 - (30581/420)*n + 121 for n>4
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EXAMPLE
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Some solutions for n=3
..0..0..0....0..0..0....0..0..0....1..1..0....0..1..0....0..0..0....0..0..0
..0..0..1....0..0..0....0..0..0....1..1..0....1..1..0....0..1..0....0..0..0
..0..1..1....1..0..0....0..1..0....1..1..0....1..1..0....1..1..0....0..1..0
..0..1..1....1..0..0....0..1..0....1..1..0....1..1..0....1..1..1....0..1..0
..0..1..1....1..1..0....1..1..1....1..1..1....1..1..0....1..1..1....1..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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