#include<iostream>
#include<fstream>
#define M 1000005
using namespace std;
long long i,c,d,nr_p, cnt[M],ma;
/*void ciur(int ma)
{
    for(int i=2;i<=ma;i++)
        {
            if(fr[i]==0)
            for(int j=i;j<=ma;j+=i)
            {
                fr[j]=1;
            }

        }
}*/
int main()
{
    freopen("mins.in","r",stdin);
    freopen("mins.out","w",stdout);
    cin>>c>>d;
    c=c-1;
    d=d-1;
    ma=max(c,d);
    for(int k=2;k<=ma;k++)
    {
        nr_p -= (cnt[k]-1)*c/k*d/k;
        for(int j=2*k; j<=ma; j+=k)
        {
            cnt[j]-=(cnt[k]-1);
        }
    }

    cout<<c*d-nr_p;
}