Counting Triangles

Time Limit: 2000/1000 MS (Java/Others)

Memory Limit: 65536/32768 K (Java/Others)

Description

Given an equilateral triangle with n the length of its side, program to count how many triangles in it.



Input

The length n (n <= 500) of the equilateral triangle's side, one per line.

process to the end of the file

Output

The number of triangles in the equilateral triangle, one per line.

Sample Input

1 2 3

Sample Output

1 5 13

Hint

Ignatius.L

Source

ZOJ Monthly, June 2003

提交代码