Divisor Sum of 345

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Example of Divisor Sum of Square-Free Integer

$\map {\sigma_1} {345} = 576$

where $\sigma_1$ denotes the divisor sum function.

Proof

We have that:

$345 = 3 \times 5 \times 23$


Hence:

\(\ds \map {\sigma_1} {345}\) \(=\) \(\ds \paren {3 + 1} \paren {5 + 1} \paren {23 + 1}\) Divisor Sum of Square-Free Integer
\(\ds \) \(=\) \(\ds 4 \times 6 \times 24\)
\(\ds \) \(=\) \(\ds 2^2 \times \paren {2 \times 3} \times \paren {2^3 \times 3}\)
\(\ds \) \(=\) \(\ds 2^6 \times 3^2\)
\(\ds \) \(=\) \(\ds \paren {2^3 \times 3}^2\)
\(\ds \) \(=\) \(\ds 24^2\)
\(\ds \) \(=\) \(\ds 576\)

$\blacksquare$