Divisor Sum of 1050

Example of Divisor Sum of Integer

 * $\map {\sigma_1} {1050} = 2976$

where $\sigma_1$ denotes the divisor sum function.

Proof
From
 * $\ds \map {\sigma_1} n = \prod_{\substack {1 \mathop \le i \mathop \le r \\ k_i \mathop > 1} } \frac {p_i^{k_i + 1} - 1} {p_i - 1} \prod_{\substack {1 \mathop \le i \mathop \le r \\ k_i \mathop = 1} } \paren {p_i + 1}$

where $n = \ds \prod_{1 \mathop \le i \mathop \le r} p_i^{k_i}$ denotes the prime decomposition of $n$.

We have that:
 * $1050 = 2 \times 3 \times 5^2 \times 7$

Hence: