Problem:
 Score : 400 points    Problem Statement 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.      Constraints  1 \leq N \leq 10^5  0 \leq K \leq N-1  All input values are integers.         Input Input is given from Standard Input in the following format:  N  K       Output Print the number of possible pairs that he may have had.        Sample Input 1 5 2      Sample Output 1 7  There are seven possible pairs: (2,3),(5,3),(2,4),(3,4),(2,5),(3,5) and (4,5) .       Sample Input 2 10 0      Sample Output 2 100       Sample Input 3 31415 9265      Sample Output 3 287927211

Solution (Python):
N, K = map(int, input().split())
ans = 0
for b in range(N + 1)[K:]:
	if b == 0:
		continue
	ans += (b - K) * int(N / b)
	if N % b >= K and K > 0:
		ans += N % b - K + 1
	elif N % b >= K:
		ans += N % b - K
print(ans)