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A223915
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Number of nX5 0..2 arrays with rows and antidiagonals unimodal and columns nondecreasing
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1
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86, 1600, 13347, 74040, 319156, 1147712, 3588729, 10031780, 25574524, 60357024, 133401811, 278664144, 554222764, 1055811684, 1936212233, 3432395716, 5902734700, 9877089124, 16123126195, 25732854408, 40234046052, 61731993272
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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) = (1009/907200)*n^10 + (1009/60480)*n^9 + (4919/30240)*n^8 + (293/288)*n^7 + (196597/43200)*n^6 + (35317/2880)*n^5 + (1341229/45360)*n^4 + (115123/3024)*n^3 + (38483/3150)*n^2 - (868/15)*n + 4 for n>2
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EXAMPLE
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Some solutions for n=3
..0..0..1..0..0....0..2..2..1..0....0..0..2..1..0....0..0..0..1..0
..0..1..2..1..0....0..2..2..1..0....0..2..2..1..0....0..1..1..2..1
..0..2..2..2..0....0..2..2..2..2....0..2..2..1..1....0..1..2..2..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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