The Problem:

The sum of the numbers from 1 to n can be defined recursively as follows:

- The sum from 1 to 1 is 1.
- The sum from 1 to n is n more than the sum from 1 to n-1.

Write a int-method named sum that accepts an int parameter, n, and **recursively** calculates and returns the sum of the numbers from 1 to n.

public int sum(int n) { if (n == 1 ) { return 1; } else { return n + sum(n-1); } }