Divisor Sum of 102

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Example of Divisor Sum of Square-Free Integer

$\map {\sigma_1} {102} = 216$

where $\sigma_1$ denotes the divisor sum function.

Proof

We have that:

$102 = 2 \times 3 \times 17$


Hence:

\(\ds \map {\sigma_1} {102}\) \(=\) \(\ds \paren {2 + 1} \paren {3 + 1} \paren {17 + 1}\) Divisor Sum of Square-Free Integer
\(\ds \) \(=\) \(\ds 3 \times 4 \times 18\)
\(\ds \) \(=\) \(\ds 3 \times \paren {2^2} \times \paren {2 \times 3^2}\)
\(\ds \) \(=\) \(\ds 2^3 \times 3^3\)
\(\ds \) \(=\) \(\ds \paren {2 \times 3}^3\)
\(\ds \) \(=\) \(\ds 216\)

$\blacksquare$