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#include <fstream>
using namespace std;
ifstream f("mins.in");
ofstream g("mins.out");
int n,m,i,j,prim[1000010];
bool pr[1000010];
long long sol;
int main()
{
f>>n>>m;
n--;m--;
if(n>m) swap(n,m);
for(i=2;i<=n;i++)
{
if(prim[i]==0)
{for(j=i;j<=n;j+=i)
prim[j]++;
if(n/i>=i)
for(j=i*i;j<=n;j+=i*i)
pr[j]=1;
}
}
for(i=1;i<=n;i++)
{
if(!pr[i])
if(prim[i]%2) sol-=1LL*(n/i)*(m/i);
else sol+=1LL*(n/i)*(m/i);
}
g<<sol;
return 0;
}