n = input()
a = map(int, raw_input().split())
a.sort()

num = [0] * 101
for x in a:
	num[x] += 1

s1, s2, s3 = 0, 0, 0
for x in num:
	s1 += x
	s2 += x * x
	s3 += x * x * x

ans = (s1 ** 3 - s1 * s2 - 2 * s1 * s2 + 2 * s3) / 6

print ans