#include <bits/stdc++.h>
using namespace std;

int find(int x, int y)
{

    for (int i = 30; i >= 0; i--) {
        if (((x >> i) & 1) && ((y >> i) & 1)) return (1 << i) - 1;
    }
    return 0;
}

int main()
{
    ios::sync_with_stdio(false), cin.tie(0);
    int t = 0;
    cin >> t;
    while (t--) {
        int n;
        cin >> n;
        vector<int> a(n + 1);
        vector<int> cnt(n + 1);
        for (int i = 1; i <= n; i++) {
            cin >> a[i];
            cnt[a[i]]++;
        }
        int mx = max_element(cnt.begin(), cnt.end()) - cnt.begin();
        int ans = cnt[mx];
        for (int i = 1; i <= n; i++) {
            if (i != mx) {
                ans = max(ans, cnt[mx] | find(cnt[mx], cnt[i]));
                ans = max(ans, cnt[mx] | cnt[i]);
            }
        }

        cout << max(ans, 1) << endl;
    }
    return 0;
}