GCD Harmonic Mean
C_K_Yang czp001 liuguangxi jtnydv25 abcd Min_25 smutley C3PO Philippe_57721 gerrob mathpseudo sinan hervas Caesum Buri nielkh
Public  09/20/14  8xp  Math  66.7% 
Let's define H(n) = Harmonic mean of GCD(n,k) for k in {1, ... , n}
For the record, if V = {V1, V2, ..., Vn} the harmonic mean of V = n/(1/V1 + 1/V2 + ... + 1/Vn}
Find H(25!)
You are given H(1050) = 52500/22403
Answer format: P/Q
[My timing : 5 sec]
For the record, if V = {V1, V2, ..., Vn} the harmonic mean of V = n/(1/V1 + 1/V2 + ... + 1/Vn}
Find H(25!)
You are given H(1050) = 52500/22403
Answer format: P/Q
[My timing : 5 sec]
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