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A082681
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Denominator of Sum_{i=n(n-1)/2+1..n(n+1)/2} 1/i.
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2
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1, 6, 60, 2520, 20020, 1627920, 124324200, 1694579040, 446626220040, 73706596563600, 35444732266944, 24569517992362200, 3290057629552053360, 551042196782556679200, 71028805196838414285360
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OFFSET
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1,2
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LINKS
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PROG
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(PARI) a(n) = denominator(sum(i = n*(n-1)/2+1, n*(n+1)/2, 1/i)); \\ Michel Marcus, Aug 29 2013
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CROSSREFS
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KEYWORD
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nonn,frac
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AUTHOR
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STATUS
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approved
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