Solving Summation Problem: Show f(n) is Not an Integer

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SUMMARY

The discussion centers on proving that the function f(n) = 1/2 + 1/3 + ... + 1/n is not an integer for any positive integer n. Participants explored various approaches, including rearranging terms and attempting to find an integer C such that C x f(n) remains non-integer. The suggestion of using induction was mentioned, although the initial case f(1) = 1 is an integer. Ultimately, the challenge lies in identifying a consistent method to demonstrate the non-integral nature of f(n) for all n greater than 1.

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Homework Statement



Let f(n) = 1/2 + 1/3 + ... + 1/n
Show that f(n) is not an integer for any positive integer n


The Attempt at a Solution



I think that rearraning/breaking down the statement might be easier than applying a theorem since it seems like a simpler problem. Simply arranging the terms got pretty messy so I think the best method is to try to find an integer C such that C x f(n) is not a integer for any value of n. I tried different ways of computing such an integer C, such as taking C to be (n-1)! or something similar for that the summation will give a bunch of integers plus one term that is not an integer but I failed to find such a value. Hopefully someone can help me out over here. Thanks.
 
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I'm a little rusty on this stuff but couldn't we solve this using induction?
 
The funny thing is [tex]f(1)=1/1[/tex] and [tex]1[/tex] is an integer. But, aside from that, IDK.
 

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