An isosceles triangle is a triangle with (at least) two equal sides.
How many isosceles triangle are possible when you are allowed to choose side length from (1,2,3....N).
Input will contain many test cases(<=10). Each on a new line.
Each Test case will give value of N<=10^8
Print number of isosceles triangle possible.
Explanation: For N=2, triangles possible are (1,1,1) ,(2,2,1) (2,2,2)