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A224151
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Number of 7Xn 0..1 arrays with rows and antidiagonals unimodal and columns nondecreasing
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1
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8, 64, 357, 1536, 5471, 16885, 46586, 117510, 275557, 608423, 1277544, 2571226, 4991541, 9394324, 17211567, 30799955, 53979914, 92858530, 157069847, 261620888, 429605663, 696147855, 1114062432, 1761895136, 2755216271, 4262322913
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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) = (1/87178291200)*n^14 + (1/4151347200)*n^13 + (1/136857600)*n^12 + (19/106444800)*n^11 + (53/12441600)*n^10 + (121/1382400)*n^9 + (1007857/609638400)*n^8 + (427321/29030400)*n^7 + (5519/62208)*n^6 + (217709/604800)*n^5 + (8736011/8553600)*n^4 + (1790117/950400)*n^3 + (90367957/37837800)*n^2 + (49717/40040)*n + 1
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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..0..0....1..1..1....0..1..0
..0..1..0....0..0..0....0..0..0....1..1..1....0..1..0....1..1..1....0..1..0
..0..1..0....0..1..0....0..0..0....1..1..1....0..1..0....1..1..1....0..1..1
..0..1..0....0..1..1....0..0..0....1..1..1....0..1..0....1..1..1....0..1..1
..0..1..1....0..1..1....0..1..1....1..1..1....1..1..0....1..1..1....1..1..1
..0..1..1....0..1..1....0..1..1....1..1..1....1..1..0....1..1..1....1..1..1
..1..1..1....1..1..1....0..1..1....1..1..1....1..1..1....1..1..1....1..1..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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