#include <fstream>
#define nm 1000001

using namespace std;

ifstream fin("mins.in");
ofstream fout("mins.out");

int vect[nm],prim[nm],c,d,n;
long long z=0,p;

int main()
{
    long long i,j;
    fin>>c>>d;
    fin.close();
    c--;d--;
    n=min(c,d);
    for(i=2; i<=n; i++)
    {
        if(!vect[i])
        {
            for(j = i; j <= n; j += i)
                vect[j]++;
            p = 1LL * i * i;
            for(j = p; j <= n; j += p)
                prim[j] = 1;
        }
        if(!prim[i])
        {
            if(!(vect[i]%2))
                z-=1LL*(c/i)*(d/i);
            else
                z+=1LL*(c/i)*(d/i);
        }
    }
    fout<<1LL*c*d-z;
    fout.close();
    return 0;
}