# import sys; input = sys.stdin.buffer.readline
# sys.setrecursionlimit(10**7)
from collections import defaultdict
con = 10 ** 9 + 7; INF = float("inf")

def getlist():
	return list(map(int, input().split()))

#処理内容
def main():
	N = int(input())
	A = getlist()
	L = [0] * 101
	for i in A:
		L[i] += 1

	ans = 0
	for i in range(101):
		for j in range(i + 1, 101):
			for k in range(j + 1, 101):
				ans += L[i] * L[j] * L[k]

	print(ans)



if __name__ == '__main__':
	main()