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A140912
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Number of 3 X 8 matrices with elements in 0..n with each row and each column in nondecreasing order. 3,8,n can be permuted, see formula.
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0
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1, 165, 9075, 259545, 4723719, 61408347, 614083470, 4971151900, 33803832920, 198520691512, 1028698128744, 4783805983320, 20239179160200, 78777112731240, 284722993157196, 963033653325810, 3068489581675375, 9262468551496875, 26617409626933125
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OFFSET
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0,2
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LINKS
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FORMULA
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(empirical) set p,q,r to n,8,3 (in any order) in s=p+q+r-1; a(n) = product {i in 0..r-1} (binomial(s,p+i)*i!/(s-i)^(r-i-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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