1에서
Warning: Undefined array key "n" in /users/2021/i2151028/public_html/2022/WebProg/ch08/exam08-05.php on line 17
까지 자연수의 합은
Warning: Undefined array key "n" in /users/2021/i2151028/public_html/2022/WebProg/ch08/exam08-05.php on line 18
0 입니다.