Revision bd6c8e64-3359-4e8c-b814-6f19d0d7b23f - Code Golf Stack Exchange

# Husk 4
```
Σṁdḣ
```
[Try it online!](https://tio.run/##yygtzv7//9zihzsbUx7uWPz//38jYxMA "Husk – Try It Online")
- `ḣ` makes a range from 1 to input
- `ṁd` flatmap digits
- `Σ` sum