Divisor Sum of 4030

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Example of Divisor Sum of Square-Free Integer

$\map {\sigma_1} {4030} = 8064$

where $\sigma_1$ denotes the divisor sum function.


Proof

We have that:

$4030 = 2 \times 5 \times 13 \times 31$


Hence:

\(\ds \map {\sigma_1} {4030}\) \(=\) \(\ds \paren {2 + 1} \paren {5 + 1} \paren {13 + 1} \paren {31 + 1}\) Divisor Sum of Square-Free Integer
\(\ds \) \(=\) \(\ds 3 \times 6 \times 14 \times 32\)
\(\ds \) \(=\) \(\ds 3 \times \paren {2 \times 3} \times \paren {2 \times 7} \times 2^5\)
\(\ds \) \(=\) \(\ds 2^7 \times 3^2 \times 7\)
\(\ds \) \(=\) \(\ds 8064\)

$\blacksquare$