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#include <bits/stdc++.h>
using namespace std;
ifstream fin("pairs.in");
ofstream fout("pairs.out");
int main() {
int n; fin >> n;
vector<int> prm(n + 1);
vector<int> ind(1e6 + 1);
for (int i = 1; i <= n; i++) {
fin >> prm[i];
ind[prm[i]] = i;
}
vector<bool> sieve(1e6 + 1);
vector<vector<int>> div(n + 1);
for (int i = 2; i <= 1e6; i++)
if (!sieve[i]) {
if (ind[i])
div[ind[i]].push_back(i);
for (int j = 2 * i; j <= 1e6; j += i) {
sieve[j] = true;
if (ind[j])
div[ind[j]].push_back(i);
}
}
vector<int> frq(1e6 + 1);
for (int i = 1; i <= n; i++)
for (int mask = 1; mask < (1 << div[i].size()); mask++) {
int prd = 1, cnt = 0;
for (int bit = 0; bit < (int) div[i].size(); bit++)
if (mask & (1 << bit)) {
prd *= div[i][bit];
cnt++;
}
frq[prd] += (cnt % 2 ? +1 : -1);
}
int64_t sol = 0;
for (int i = 2; i <= 1e6; i++)
if (frq[i] < 0)
sol -= 1LL * -frq[i] * (-frq[i] - 1) / 2;
else
sol += 1LL * +frq[i] * (+frq[i] - 1) / 2;
fout << 1LL * n * (n - 1) / 2 - sol << '\n';
fout.close();
return 0;
}