#include <iostream>
#include <fstream>
#include <algorithm>
using namespace std;
ifstream f ("mins.in");
ofstream g ("mins.out");
long long vek[1000001];
bool ispp[1000002];
long long m,n,i,j;
int main()
{
    f>>m>>n;
    long long nonc=0;
    m--;
    n--;

        long long s=0;

    if(n>m) swap(m,n);

    for(i=2;i<=n;++i)
    {
       // cout<<"u";

        if(vek[i]==0){
            for(j=i;j<=n;j+=i)
            {
             //   cout<<"v";
                vek[j]++;

            }
            long long pp=i*i;
            for(j=pp;j<=n;j+=pp)
                ispp[j]=true;

        }
        if(!ispp[i])
        {
            if(vek[i]%2==1) s+=1LL*((m/i)*(n/i));
            else s-=1LL*((m/i)*(n/i));
        }

    }

    g<<1LL*(m)*(n)-s;




    return 0;
}