n = int(input())
A = list(map(int, input().split()))

ans = 0

for t in range(1, 31):
    B = [a - t for a in A]
    tot = 0
    cnt = 1
    for b in B:
        if b == 0:
            ans += cnt
            cnt += 1
        tot += b


print(n * (n + 1) // 2 - ans + 1)