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#include <bits/stdc++.h>
#pragma optimize GCC ("Ofast")
#pragma GCC optimize("O3")
#pragma GCC optimize("unroll-loops")
///#include <tryhardmode>
///#include <GODMODE::ON>
using namespace std;
ifstream fin ("pairs.in");
ofstream fout ("pairs.out");
const int NMAX=1e6+5;
int mobius[NMAX];
bool ciur[NMAX];
int freq[NMAX];
int lpf[NMAX];
void precompute_mobius()
{
int i,j;
lpf[1]=mobius[1]=1;
for(i=2;i<=NMAX-3;i++)
{
if(!ciur[i])
{
for(j=i;j<=NMAX-3;j+=i)
{
ciur[j]=true;
lpf[j]=i;
}
}
}
for(i=2;i<=NMAX-3;i++)
{
if(lpf[i/lpf[i]]==lpf[i])
mobius[i]=0;
else
mobius[i]=-mobius[i/lpf[i]];
}
}
signed main()
{
ios_base::sync_with_stdio(false);
fin.tie(NULL);
fout.tie(NULL);
int n,i,j;
long long ans=0;
fin>>n;
for(i=1;i<=n;i++)
{
int x;
fin>>x;
freq[x]++;
}
precompute_mobius();
for(i=1;i<=NMAX-3;i++)
{
int kon=0;
for(j=i;j<=NMAX-3;j+=i)
kon+=freq[j];
ans+=1LL*mobius[i]*kon*(kon-1)/2;
}
fout<<ans;
fin.close();
fout.close();
return 0;
}