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#include <bits/stdc++.h>
using namespace std;
ifstream in ("mins.in");
ofstream out ("mins.out");
const int LIM = 1e6 + 9;
int miu[LIM];
vector < int > primes;
int ciur[LIM];
int n, m;
long long ans;
int main()
{
ciur[1] = 1;
miu[1] = 1;
for ( int i = 2 ; i < LIM ; ++i )
{
if ( ciur[i] == 0 )
{
primes.push_back (i);
ciur[i] = i;
}
miu[i] = -miu[i / ciur[i]];
if ( ciur[i] == ciur [i / ciur[i]] )
miu[i] = 0;
for ( int j = 0 ; j < primes.size () && i * primes[j] < LIM && primes[j] <= ciur[i] ; ++j )
ciur[i * primes[j]] = primes[j];
}
in >> n >> m;
--n;
--m;
if ( n > m )
swap ( n, m );
for ( int i = 1 ; i <= n ; ++i )
ans += 1LL * ( n / i ) * ( m / i ) * miu[i];
out << ans;
return 0;
}