# Tau function

• April 13th 2012, 06:19 AM
Fernando
Tau function
Hello.

If n is a positive integer, show that the equation $\sigma(x)=n$ has a finite number of solutions.

Thanks.

PD: $\sigma(n)=\prod_{i=1}^k{\frac{p_i^{n_i+1}-1}{p_i-1}}$