Divisor Sum of Non-Square Semiprime/Examples/94/Proof 2

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Example of Divisor Sum of Non-Square Semiprime

$\map {\sigma_1} {94} = 144$


Proof

We have that:

$94 = 2 \times 47$

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


Hence:

\(\ds \map {\sigma_1} {94}\) \(=\) \(\ds \paren {2 + 1} \paren {47 + 1}\) Divisor Sum of Non-Square Semiprime
\(\ds \) \(=\) \(\ds 3 \times 48\)
\(\ds \) \(=\) \(\ds 3 \times \paren {2^4 \times 3}\)
\(\ds \) \(=\) \(\ds 2^4 \times 3^2\)
\(\ds \) \(=\) \(\ds \paren {2^2 \times 3}^2\)
\(\ds \) \(=\) \(\ds 12^2\)
\(\ds \) \(=\) \(\ds 144\)

$\blacksquare$