Problem Statement

Given integers L and L,R\ $(L \le R),$ find the number of pairs (x,y) of integers satisfying all of the conditions below:

• $L \le x,y \le R$
• Let g be the greatest common divisor of x and y. Then, the following holds.
• $g \neq 1, \frac{x}{g} \neq 1$, and $\frac{y}{g} \neq 1$.

Input

Input is given from Standard Input in the following format:
L R

Output

Print the answer as an integer.

Constraints

• All values in input are integers.
• $1 \le L \le R \le 10^6$

Sample Input 1

3 7

Sample Output 1

2

Let us take some number of pairs of integers, for example.

• (x,y)=(4,6) satisfies the conditions.
• (x,y)=(7,5) has g=1 and thus violates the condition.
• $(x,y)=(6,3) has \frac{y}{g}=1$ and thus violates the condition.

There are two pairs satisfying the conditions: (x,y)=(4,6),(6,4).

Sample Input 2

4 10

Sample Output 2

12

Sample Input 3

1 1000000

Sample Output 3

392047955148

见题面 Input 部分

见题面 Output 部分