Thanks, but let me clarify that a) the sum in question is infinite, and b) all powers (whose reciprocals appear in the sum) are >= 2. --Dan Bob Baillie wrote: << i don't know about a sum that equals 3/5, but there are the following sums of harmonic numbers that unexpectedly sum to 2 and 6: http://www.math.ubc.ca/~gerg/papers/downloads/recsum2.pdf http://www.math.ubc.ca/~gerg/papers/downloads/recsum6.pdf bob baillie --- I wrote: << A few years ago I read in some math journal that a certain sum of reciprocal integer powers has an unexpectedly simple sum -- I think it was 3/5. But I can't find the article or a reference to this fact. So I don't know just which reciprocal integer powers are being summed (or whether 3/5 is right). Can anyone give me a pointer to this result?

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