for _ in range(int(input())):
    n = int(input())
    a = list(map(int,input().split()))
    ans = "Yes" if a[0]!=a[-1] else "No"
    b = [i for i in range(n) if a[i]!=a[0]]
    if len(b)>3: ans = "Yes"
    for i in range(len(b)-1):
        if b[i]+1==b[i+1]: ans = "Yes"
    print(ans)