Function mul

mul(formula: (n: number) => number, inf: number, sup: number): number
Returns the product of a sequence.
Parameters
- formula: (n: number) => number
  Sequence written in product notation
- inf: number
  Lower bound
- sup: number
  Upper bound
Returns number
Example
```
// Returns 120
const mul = Chalkboard.numb.mul((n) => n + 1, 0, 5);
```
- Defined in Chalkboard.numb.ts:681