Score : 400 points
Takahashi had a pair of two positive integers not exceeding N, (a,b), which he has forgotten. He remembers that the remainder of a divided by b was greater than or equal to K. Find the number of possible pairs that he may have had.
Input is given from Standard Input in the following format:
N K
Print the number of possible pairs that he may have had.
5 2
7
There are seven possible pairs: (2,3),(5,3),(2,4),(3,4),(2,5),(3,5) and (4,5).
10 0
100
31415 9265
287927211