olimp

import java.util.*;
import java.io.IOException;
public class olimp4 {
    public static void main (String[] args) throws IOException
    {
Scanner in = new Scanner(System.in);
        long a = in.nextLong(), b = in.nextLong(),c = in.nextLong(),max=0;
        for (long i = 1; i <=a/c; i++) {
        if((i*c)%b==0)continue;
         max+=i*c;
        }
        long t1 = a/b;
        if(t1%2==1)max+=(t1+1)*b/2;
        max+=t1/2*(t1+1)*b;
        System.out.println(max%1000000007);
    }
}