#include <iostream>
#include <fstream>
#define MAX 1000005
using namespace std;
ifstream f("mins.in");
ofstream g("mins.out");
int n,m,k,sol,a[MAX],b[MAX];
void read() { f>>n>>m; n--; m--; k=min(n,m); }
void solve()
{
    int i,j; sol=n*m;
    for(i=2;i<=k;i++)
    {
        if(a[i]==0)
        {
            for(j=i;j<=n;j+=i)++a[j];
            if(i*i<=n)for(j=i*i;j<=n;j+=i*i)b[j]=1;
        }
        if(b[i]==0)if(a[i]%2==1)sol-=(n/i)*(m/i); else sol+=(n/i)*(m/i);
    }
    g<<sol;
}
int main()
{
    read();solve();
    return 0;
}