3877.Little Elephant and Triangle

Time Limit: 1s Memory Limit: 256MB

The Little Elephant is playing with the Cartesian coordinates' system. Most of all he likes playing with integer points. The Little Elephant defines an integer point as a pair of integers (x;y), such that 0 \le x \le w and 0 \le y \le h. Thus, the Little Elephant knows only (w+1) \cdot (h+1) distinct integer points.

The Little Elephant wants to paint a triangle with vertexes at integer points, the triangle's area must be a positive integer. For that, he needs to find the number of groups of three points that form such triangle. At that, the order of points in a group matters, that is, the group of three points (0;0), (0;2), (2;2) isn't equal to the group (0;2), (0;0), (2;2).

Help the Little Elephant to find the number of groups of three integer points that form a nondegenerate triangle with integer area.

Input Format(From the terminal/stdin)

A single line contains two integers w and h (1 \le w,h \le 4000).

Output Format(To the terminal/stdout)

In a single output line print an integer - the remainder of dividing the answer to the problem by 1000000007 (109+7).

Sample Input 1

Copy
2 1
 · \n

Sample Output 1

Copy
36
  \n

Sample Input 2

Copy
2 2
 · \n

Sample Output 2

Copy
240
   \n

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