x= int(input())
for _ in range(x):
    n = int(input())
    l = list(map(int,input().split()))
    count = 0
    flag= True
    while flag:
        flag = True
        for i in range(n-1):
            if l[i] >= l[i+1]:
                flag = False
                break
        if flag == True:
            break
        if flag == False:
            count += 1
            for i in range(n):
                l[i] += i+1
            flag = True