Sum of Remainders

2000ms

262144K

Description:

Calculate the value of the sum: n mod 1 + n mod 2 + n mod 3 + ... + n mod m. As the result can be very large, you should print the value modulo 10⁹ + 7 (the remainder when divided by 10⁹ + 7).

The modulo operator a mod b stands for the remainder after dividing a by b. For example 10 mod 3 = 1.

Input:

The only line contains two integers n, m (1 ≤ n, m ≤ 10¹³) — the parameters of the sum.

Output:

Print integer s — the value of the required sum modulo 10⁹ + 7.

Sample Input:

3 4

Sample Output:

Sample Input:

4 4

Sample Output:

Sample Input:

1 1

Sample Output:

Informação

Provedor Codeforces

Código CF616E