#include<stdio.h>

int v[1000002];

long long min(long long a,long long b)
{
    return a<b?a:b;
}

int main()
{
    freopen("mins.in","r",stdin);
    freopen("mins.out","w",stdout);
    long long n,m,i,j,s=0,max,p,n1,m1;
    scanf("%lld%lld",&n,&m);
    n1=n-1;
    m1=m-1;
    max=min(n,m)-1;
    for(i=2;i<=max;++i)
    {
        if(v[i]==0)
        {
            for(j=i;j<=max;j+=i)
                ++v[j];
            p=i*i;
            for(j=p;j<=max;j+=p)
                v[j]=-2000000000;
        }
        if(v[i]>0)
            if(v[i]&1)
                s-=(n1/i)*(m1/i);
            else
                s+=(n1/i)*(m1/i);
    }

    printf("%lld\n",s+n1*m1);
    return 0;
}