Divisor Sum of 710

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Example of Divisor Sum of Integer

$\map {\sigma_1} {710} = 1296$

where $\sigma_1$ denotes the divisor sum function.


Proof

We have that:

$710 = 2 \times 5 \times 71$


Hence:

\(\ds \map {\sigma_1} {710}\) \(=\) \(\ds \paren {2 + 1} \paren {5 + 1} \paren {71 + 1}\) Divisor Sum of Square-Free Integer
\(\ds \) \(=\) \(\ds 3 \times 6 \times 72\)
\(\ds \) \(=\) \(\ds 3 \times \paren {2 \times 3} \times \paren {2^3 \times 3^2}\)
\(\ds \) \(=\) \(\ds 2^4 \times 3^4\)
\(\ds \) \(=\) \(\ds \paren {2^2 \times 3^2}^2\)
\(\ds \) \(=\) \(\ds 1296\)

$\blacksquare$