#include <iostream>
#include <fstream>
#include <algorithm>
using namespace std;
ifstream f ("mins.in");
ofstream g ("mins.out");
int vek[1000001];
int cek[1000001];
int m,n;
int main()
{
    f>>m>>n;
    int nonc=0;
    if(n>m) swap(m,n);

    for(int i=2;i<n;++i)
    {
        int px=0, py=0,j;
        if(vek[i]==0){
            for(j=2*i;j<m;j+=i)
            {
                vek[i]=1;
                px++;

            }
            for(j=2*i;j<n;j+=i)
            {

                py++;
            }

        }
        nonc+=(py+1)*(px+1);
    }
    g<<(m-1)*(n-1)-nonc;




    return 0;
}