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Let $g$ be an arithmetic function satisfying

$\sum_{d|n} g(d) = \frac{n-1}{n+1}$

Find $g(24)$

I have a feeling moebius inversion is going to be used.

Really I am just not sure what this is looking for. I don't know how to interpret $g(24)$

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Your feeling is right. What do you intend to do about it? –  vonbrand Mar 4 at 2:02
Haven't the foggiest. I really dont know what I am looking for. –  Skuttle_Butt Mar 4 at 2:05
Check Wikipedia, where all truths (and all lies) are recorded. –  vonbrand Mar 4 at 2:11
Going through all the motions I got $\frac{-5686}{2925}$ –  Skuttle_Butt Mar 4 at 3:03
Then publish the details as an answer to your own question, wait a bit for any critics to come out of the woodwork, and if nothing better shows up, accept your answer. –  vonbrand Mar 4 at 12:45

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