Divisor Sum of 382

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Example of Divisor Sum of Non-Square Semiprime

$\map {\sigma_1} {382} = 576$

where $\sigma_1$ denotes the divisor sum function.


Proof

We have that:

$382 = 2 \times 191$

and so by definition is a semiprime whose prime factors are distinct.


Hence:

\(\ds \map {\sigma_1} {382}\) \(=\) \(\ds \paren {2 + 1} \paren {191 + 1}\) Divisor Sum of Non-Square Semiprime
\(\ds \) \(=\) \(\ds 3 \times 192\)
\(\ds \) \(=\) \(\ds 3 \times \paren {2^6 \times 3}\)
\(\ds \) \(=\) \(\ds 2^6 \times 3^2\)
\(\ds \) \(=\) \(\ds \paren {2^3 \times 3}^2\)
\(\ds \) \(=\) \(\ds 24^2\)
\(\ds \) \(=\) \(\ds 576\)

$\blacksquare$