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#include <iostream>
#include <fstream>
#include <cstring>
using namespace std;
ifstream f("mins.in");
ofstream g("mins.out");
int n,m,nr[1000005],ciur[1000005],minim,maxim,cap;
long long sum;
int main()
{
f>>n>>m;
n--; m--;
minim=min(n,m); maxim=max(n,m);
for(int i=2;i<=minim;i++)
ciur[i]=1;
sum+=1LL*(maxim-1)*(maxim)/2-1LL*(maxim-minim)*(maxim-minim+1)/2+1LL*(minim-2)*(minim-1)/2+1LL*(n+m-1);
for(int i=2;i<=minim;i++)
{
if(ciur[i]==1)
for(int j=i;j<=minim;j+=i)
{
ciur[j]*=i;
nr[j]++;
}
if(ciur[i]==i)
{
cap=maxim/i-minim/i;
if(nr[i]%2==1)
sum-=1LL*(maxim/i)*(maxim/i+1)/2-1LL*cap*(cap+1)/2+1LL*(minim/i-1)*(minim/i)/2;
else
sum+=1LL*(maxim/i)*(maxim/i+1)/2-1LL*cap*(cap+1)/2+1LL*(minim/i-1)*(minim/i)/2;
}
}
g<<sum;
}