Divisor Sum of Non-Square Semiprime/Examples/35

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Example of Divisor Sum of Non-Square Semiprime

$\map {\sigma_1} {35} = 48$

where $\sigma_1$ denotes the divisor sum function.


Proof

We have that:

$35 = 5 \times 7$

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


Hence:

\(\ds \map {\sigma_1} {35}\) \(=\) \(\ds \paren {5 + 1} \paren {7 + 1}\) Divisor Sum of Non-Square Semiprime
\(\ds \) \(=\) \(\ds 6 \times 8\)
\(\ds \) \(=\) \(\ds 48\)

$\blacksquare$