#include <iostream>
#include <fstream>
using namespace std;
ifstream f("mins.in");
ofstream g("mins.out");
const int MAX = 1000001;
int ciurn[MAX],c,d,n;
bool ciurp[MAX];
long long card;
void calcul(int i)
{
    if(ciurn[i] == 0)
    {
        for(int j = i; j <= n; j += i)
            ciurn[j]++;
        long long k = 1LL * i * i;
        for(long long jj = k; jj <= n; jj += k)
            ciurp[jj] = 1;
    }
    if(ciurp[i] == 0)
    {
        long long t = 1LL * (c / i) * (d / i);
        if(ciurn[i] % 2 == 0)
            card -= t;
        else
            card += t;
    }
}
int main()
{
    f>>c>>d;
    c--;
    d--;
    n=min(c,d);
    for(int i=2;i<=n;i++)
        calcul(i);
    g<<1LL*c*d-card<<'\n';
    f.close();
    g.close();
    return 0;
}