from collections import defaultdict

def check(x):
    n = N
    for v in dic.values():
        if v > x:
            n -= v - x
    return n >= 3 * x

for _ in range(int(input())):
    N = int(input())
    L = list(map(int, input().split()))
    dic = defaultdict(int)
    for l in L:
        dic[l] += 1
    lb = 0
    ub = N // 3 + 1
    while ub - lb > 1:
        mid = (ub + lb) // 2
        if check(mid):
            lb = mid
        else:
            ub = mid
    print(lb)