Math Table or Method of Solving an infinite sum of reciprocal powers

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The discussion centers on solving the infinite sum of the reciprocals of the squares of all positive odd integers, specifically the sum ∑(1/n^2) for odd n. Participants clarify that the correct answer is π²/8, not π²/6, which is the value for the sum of all positive integers. To derive this, one can split the total sum into even and odd components and relate the even series back to the Riemann zeta function. The conversation emphasizes the need for understanding the even series to complete the calculation. Overall, the thread highlights the mathematical approach to finding the sum of reciprocal powers for odd integers.
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Is anybody aware of how to solve the following infinite sum:

\sum\frac{1}{n^2} for all positive odd integers?



Is this the sort of thing you just look up in a math table or solve?

If math table, do I need a "sum of reciprocal powers" table or a "riemann zeta function" table?

If solve - how?

I know the answer is pi^2 / 8 but I haven't a clue how to calculate that and cannot find a math table with the appropriate functions.
 
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This is the Riemann zeta function Zeta(2), by definition. It's actually equal to pi^2/6, not pi^2/8, and Euler found a clever way of showing this, which is detailed here:

http://en.wikipedia.org/wiki/Basel_problem
 
phyzguy said:
This is the Riemann zeta function Zeta(2), by definition. It's actually equal to pi^2/6, not pi^2/8, and Euler found a clever way of showing this, which is detailed here:

http://en.wikipedia.org/wiki/Basel_problem

No, it's pi^2/8. Not zeta(2). The OP asked for the sum over odd integers. Split the sum over all integers into the sum over even integers and the sum over odd and equate it to zeta(2). Now find a way to relate the sum over even integers to zeta(2).
 
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Sorry, I missed the "odd". You're right.
 
That makes sense, since the even series is not hard to find. I was thinking about this earlier today and haven't done the calculation yet, but I'm glad to have some reinforcement on that path.

Now I get to have fun learning the even series.

thx
 
Question: A clock's minute hand has length 4 and its hour hand has length 3. What is the distance between the tips at the moment when it is increasing most rapidly?(Putnam Exam Question) Answer: Making assumption that both the hands moves at constant angular velocities, the answer is ## \sqrt{7} .## But don't you think this assumption is somewhat doubtful and wrong?

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