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Need help in Harmonic series
Difference between en1 and en2, changed 2 character(s)
I heard that  it is possible to compute $\sum\limits_{i=1}^n\frac{1}{ni}\pmod{998244353}$ in $O(\sqrt n)$ complexity with some polynomial technology .↵
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But I don't know how. Can someone give a solution ?

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  Rev. Lang. By When Δ Comment
en2 English zero4338 2021-11-03 02:32:10 2 Tiny change: 'n\frac{1}{n}\pmod{998' -> 'n\frac{1}{i}\pmod{998'
en1 English zero4338 2021-11-01 09:38:09 232 Initial revision (published)