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A076175
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Denominator of sum( i+j+k = n, (i*j)/k) i,j,k >=1.
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2
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1, 1, 1, 2, 3, 12, 15, 30, 21, 168, 126, 1260, 990, 792, 1287, 18018, 5005, 80080, 68068, 58344, 50388, 201552, 176358, 3879876, 3432198, 27457584, 24515700, 637408200, 573667380, 16062686640, 29113619535, 26466926850, 24131609775
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OFFSET
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1,4
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LINKS
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PROG
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(PARI) a(n)=denominator(sum(i=1, n, sum(j=1, n, sum(k=1, n, if(n-i-j-k, 0, 1)*i*j/k))))
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CROSSREFS
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KEYWORD
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frac,nonn
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AUTHOR
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STATUS
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approved
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