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A215176
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Number of nXnXn triangular 0..2 arrays with every horizontal row nondecreasing, first elements of rows nonincreasing, last elements of rows nondecreasing, and every row having the same average value
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1
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3, 4, 5, 9, 17, 48, 141, 559, 2231, 11148, 55733, 334389, 2006325, 14044264, 98309837, 786478683, 6291829451, 56626465044, 509638185381, 5096381853793, 50963818537913, 560602003917024, 6166622043087245, 73999464517046919
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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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EXAMPLE
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Some solutions for n=4
.....1........1........1........2........0........1........1........1
....1.1......1.1......1.1......2.2......0.0......1.1......0.2......1.1
...1.1.1....1.1.1....0.1.2....2.2.2....0.0.0....1.1.1....0.1.2....0.1.2
..0.0.2.2..0.1.1.2..0.0.2.2..2.2.2.2..0.0.0.0..1.1.1.1..0.0.2.2..0.1.1.2
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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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