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#include <cstdio>
#include <cstring>
#include <cstdlib>
#include <ctime>
#include <cmath>
#include <vector>
#include <algorithm>
#include <queue>
using namespace std;
int n, m, i, j, aux, o, k, q, w;
long long r;
char a[1000005], v[1000005], pp[1000005];
int main()
{
freopen("mins.in", "r", stdin);
freopen("mins.out", "w", stdout);
scanf("%d%d", &n, &m);
n--;m--;
if(n>m)
{
m+=n;
n=m-n;
m=m-n;
}
r=1LL*n*m;
for(i=2;i<=n;i++)
{
if(!v[i])
{
for(j=i+i;j<=n;j+=i)
v[j]=1, a[j]++;
a[i]=1;
if(1LL*i*i<=n)
for(j=i*i;j<=n;j+=i*i)
pp[j]=1;
}
}
for(i=2;i<=n;i++)
{
if(pp[i]) continue;
if(a[i]&1)
r-=(n/i)*(m/i);
else
r+=(n/i)*(m/i);
}
printf("%lld", r);
return 0;
}