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#include<bits/stdc++.h>
#define god dimasi5eks
#pragma GCC optimize("O3")
#define fi first
#define se second
#define pb push_back
#define pf push_front
#define fisier 1
using namespace std;
typedef long long ll;
const int mod = 1000000007;
const double dancila = 3.14159265359; // PI
const double eps = 1e-9;
int n, fr[1000002], val, maxval;
ll cnt[1000002], ans;
int main()
{
#ifdef fisier
ifstream cin("pairs.in");
ofstream cout("pairs.out");
#endif
ios_base::sync_with_stdio(false);
cin.tie(NULL);
cin >> n;
for(int i = 1; i <= n; ++i)
{
cin >> val;
fr[val]++;
maxval = max(maxval, val);
}
ans = 1LL * n * (n-1) / 2;
for(int i = maxval; i >= 2; --i)
{
val = 0;
for(int j = i; j <= maxval; j += i)
{
val += fr[j];
cnt[i] -= cnt[j];
}
cnt[i] += 1LL * val * (val-1) / 2;
ans -= cnt[i];
}
cout << ans;
return 0;
}