Given the value of N, you will have to find the value of G. The definition of G is given below:

G =\sum_{i=1}^{i<N} \sum_{j=i+1}^{j≤N} GCD(i, j)

Here GCD(i, j) means the greatest common divisor of integer i and integer j. For those who have trouble understanding summation notation, the meaning of G is given in the following code:

G=0;
for(i=1;i<N;i++)
for(j=i+1;j<=N;j++)
{
    G+=GCD(i,j);
}
/*Here GCD() is a function that finds
the greatest common divisor of the two
input numbers*/

For each line of input produce one line of output. This line contains the value of G for corresponding N.