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A224358
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Number of 7Xn 0..2 arrays with diagonals and antidiagonals unimodal and rows nondecreasing
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1
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2187, 279936, 2710892, 11704964, 37433596, 107694133, 300892325, 834305212, 2288859662, 6150132424, 16041429234, 40392369273, 97941685953, 228592108824, 513973817853, 1114992467592, 2338135911280, 4749060805124, 9361861348424
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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) = (118519/21794572800)*n^14 + (2257/124540416)*n^13 + (126449/119750400)*n^12 + (175069/21772800)*n^11 + (49727/544320)*n^10 + (1018841/1451520)*n^9 + (447386489/76204800)*n^8 + (2968546327/21772800)*n^7 - (29364148727/21772800)*n^6 + (37983445967/2177280)*n^5 - (4238661826723/59875200)*n^4 + (1152210830677/3326400)*n^3 - (7620593288311/18918900)*n^2 + (1232004733/910)*n - 8483920 for n>9
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EXAMPLE
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Some solutions for n=3
..0..0..0....0..0..0....0..0..0....0..0..0....0..0..0....0..0..0....0..0..0
..0..0..2....0..0..2....0..0..1....0..1..2....0..1..1....0..1..1....0..1..1
..0..0..2....0..1..1....0..0..2....0..0..0....0..1..2....0..0..1....0..0..0
..0..0..0....0..1..2....0..2..2....0..0..1....0..0..0....0..1..2....0..0..0
..0..0..2....0..0..1....0..2..2....0..1..1....0..0..2....1..1..2....0..2..2
..0..0..1....0..1..1....0..0..1....0..0..2....2..2..2....1..1..1....0..0..1
..0..1..1....1..1..2....0..2..2....0..2..2....0..1..1....0..1..2....0..0..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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