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

using is = int32_t;
using il = int64_t;
using us = uint32_t;
using ul = uint64_t;

template<class T> void mes(T *arr, us n=1, us b=0) { memset(arr, b, n*sizeof(T)); }
// -------------------------
con us MX = 1e5 + 7;

us n, cnt[MX];

void solve() {
    us l = cnt[0], r = cnt[cnt[0]!=n];
    us v = (l&r);
    while(v!=(v&-v)) v -= v&-v;
    cout << ((l|r)|(v-1));
}

void pre() {
    cin >> n;
    for(us i=0, c; i<n; ++i) {
        cin >> c;
        ++cnt[c-1];
    }
    sort(cnt, cnt+n, greater<>());
}

void aft() {
    mes(cnt, n);
    cout << '\n';
}

us _t = 1;
void init() {
    ios::sync_with_stdio(0);
    cin.tie(0); cout.tie(0);
    cin >> _t;
}

int main() {
    init();
    for(us i=1; i<=_t;) {
        pre(); solve();
        ++i<=_t?aft():exit(0);
    }
}