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A117508
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Denominators of partial sums of the Brun series divided by 5.
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1
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3, 21, 3003, 969969, 872002131, 1537339756953, 5532885785273847, 28676947025074349001, 298326279901848452657403, 3479379402495258503343291189, 66257821961717207679166294112127
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OFFSET
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1,1
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COMMENTS
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Numerators divided by 4 are given by A117507.
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LINKS
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FORMULA
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a(n)=denominator(r(n))/5, with r(n):=sum(1/ltp(k) + 1/(ltp(k)+2),k=1..n), n>=1, with ltp(k):=A001359(k) (lesser twin primes).
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CROSSREFS
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KEYWORD
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nonn,easy,frac
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AUTHOR
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STATUS
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approved
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