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A184709
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Number of strings of numbers x(i=1..9) in 0..n with sum i*x(i) equal to n*9
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1
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8, 91, 580, 2574, 8939, 26146, 67105, 155645, 332729, 665317, 1257898, 2268061, 3925640, 6557703, 10618287, 16725802, 25706637, 38648840, 56963074, 82456645, 117416301, 164706836, 227880334, 311304767, 420304310, 561323415, 742104234
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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)=a(n-1)+a(n-2)+a(n-3)-a(n-4)-2*a(n-5)-a(n-7)+a(n-8)-a(n-9)+a(n-10)+a(n-11)+3*a(n-12)+a(n-13)-a(n-14)-a(n-15)-2*a(n-16)-a(n-17)-3*a(n-18)+3*a(n-21)+a(n-22)+2*a(n-23)+a(n-24)+a(n-25)-a(n-26)-3*a(n-27)-a(n-28)-a(n-29)+a(n-30)-a(n-31)+a(n-32)+2*a(n-34)+a(n-35)-a(n-36)-a(n-37)-a(n-38)+a(n-39)
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EXAMPLE
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Some solutions for n=3
..3....2....1....3....1....2....1....3....0....0....1....0....1....1....0....0
..0....2....1....3....0....0....2....1....2....1....0....1....3....1....0....0
..2....3....0....0....0....1....3....0....0....3....3....0....2....0....2....0
..0....1....1....0....1....0....2....1....0....2....3....1....2....2....0....1
..0....0....0....0....2....3....1....1....3....0....1....0....0....0....1....2
..0....0....2....0....2....0....0....1....0....0....0....2....1....0....0....1
..0....0....0....0....0....1....0....1....0....0....0....0....0....1....1....1
..0....1....1....0....0....0....0....0....1....1....0....0....0....0....0....0
..2....0....0....2....0....0....0....0....0....0....0....1....0....1....1....0
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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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