//check check check
#include<iostream>
#include<vector>
#include<algorithm>
#include<fstream>
#include<queue>
#include<cstring>
#include<map>
#include<iomanip>

#define ll long long
#define pb(x) push_back(x)

using namespace std;

typedef pair<int,int> ii;

const int NMAX = 1e6+5;

bool viz[NMAX];
ll cnt[NMAX];

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

int main()
{
    ll i,j,c,d;

    fin>>c>>d;
    if(c > d)
        swap(c,d);
    --c;
    --d;
    ll perechiCompuse = 0;
    for(i = 2 ; i <= c ; ++i)
    {
        if(!viz[i])
        {
            for(j = i ; j <= c ; j += i)
                cnt[j]++ , viz[j] = 1;
        }
        if(cnt[i]&1)
            perechiCompuse += (c/i) * (d/i);
        else
            perechiCompuse -= (c/i) * (d/i);
    }

    fout<< c*d - perechiCompuse;

    return 0;
}