1: /** @param n An integer > 0. 2: @return The sum 1 + 2 + ... + n. */ 3: public static int sumOf(int n) 4: { 5: int sum; 6: if (n == 1) 7: sum = 1; // Base case 8: else 9: sum = sumOf(n - 1) + n; // Recursive call 10: 11: return sum; 12: } // end sumOf 13: // Version 4.0