void solve() {
    int n; cin >> n;
    vi a(n); cin >> a;
    int k = *max_element(all(a)) + 1;

    vector<vector<int>> del(k);
    for (int i = 1; i < k; ++i) {
        for (int j = i; j < k; j += i) {
            del[j].push_back(i);
        }
    }
    vector<int> cnt(k);
    for (int i = 0; i < n; ++i) {
        for (int j : del[a[i]]) {
            cnt[j]++;
        }
    }
    vector<long long> ans(k);
    for (int i = 0; i < k; ++i) {
        ans[i] = 1ll * cnt[i] * (cnt[i] - 1) / 2;
    }
    for (int i = k - 1; i >= 0; --i) {
        for (int j : del[i]) {
            if (j != i) {
                ans[j] -= ans[i];
            }
        }
    }
    cout << ans[1];
}