Divisor Sum of 17,325
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Example of Divisor Sum of Integer
- $\map {\sigma_1} {17 \, 325} = 38 \, 688$
where $\sigma_1$ denotes the divisor sum function.
Proof
We have that:
- $17 \, 325 = 3^2 \times 5^2 \times 7 \times 11$
Hence:
\(\ds \map {\sigma_1} {17 \, 325}\) | \(=\) | \(\ds \dfrac {3^3 - 1} {3 - 1} \times \dfrac {5^3 - 1} {5 - 1} \times \paren {7 + 1} \times \paren {11 + 1}\) | Divisor Sum of Integer | |||||||||||
\(\ds \) | \(=\) | \(\ds \dfrac {26} 2 \times \dfrac {124} 4 \times 8 \times 12\) | ||||||||||||
\(\ds \) | \(=\) | \(\ds 13 \times 31 \times 8 \times 12\) | ||||||||||||
\(\ds \) | \(=\) | \(\ds 13 \times 31 \times 2^3 \times \paren {2^2 \times 3}\) | ||||||||||||
\(\ds \) | \(=\) | \(\ds 2^5 \times 3 \times 13 \times 31\) | ||||||||||||
\(\ds \) | \(=\) | \(\ds 38 \, 688\) |
$\blacksquare$