Divisor Sum of 742

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Example of Divisor Sum of Integer

$\map {\sigma_1} {742} = 1296$

where $\sigma_1$ denotes the divisor sum function.


Proof

We have that:

$742 = 2 \times 7 \times 53$


Hence:

\(\ds \map {\sigma_1} {742}\) \(=\) \(\ds \paren {2 + 1} \paren {7 + 1} \paren {53 + 1}\) Divisor Sum of Square-Free Integer
\(\ds \) \(=\) \(\ds 3 \times 8 \times 54\)
\(\ds \) \(=\) \(\ds 3 \times 2^3 \times \paren {2 \times 3^3}\)
\(\ds \) \(=\) \(\ds 2^4 \times 3^4\)
\(\ds \) \(=\) \(\ds \paren {2^2 \times 3^2}^2\)
\(\ds \) \(=\) \(\ds 1296\)

$\blacksquare$