import sys
from functools import lru_cache

input = sys.stdin.buffer.readline

sys.setrecursionlimit(4100000)
n = int(input())
A = list(map(int, input().split()))

A.sort(reverse=True)


# @lru_cache(None)
# def calc(bit):
#     # print("bit", bit)
#     if bit == (1 << n) - 1:
#         return 1
#     res = 0
#     mx = -1
#     for i in range(n):
#         if (bit >> i) & 1:
#             mx = max(mx, A[i])
#     ok = 0
#     ng = 0
#     for i in range(n):
#         if (bit >> i) & 1:
#             continue
#         if A[i] >= mx:
#             ok += 1
#         else:
#             ng += 1
#     assert ok + ng > 0
#     # ratio = 1 / (ok + ng)
#     prod = 1
#     if ng:
#         return 0
#     if not ok:
#         return 0
#     for i in range(n):
#         if (bit >> i) & 1:
#             continue
#         nbit = bit | (1 << i)
#         if A[i] >= mx:
#             prod *= calc(nbit)
#     goukei = 0
#     for i in range(n):
#         if (bit >> i) & 1:
#             continue
#         nbit = bit | (1 << i)
#         if A[i] >= mx:
#             goukei += prod // calc(nbit)
#     print("bit", bin(bit), "prod", prod, "goukei", goukei)
#     res = (ok + ng) * prod // goukei
#     return res


# cnt = 100
# ok = 1
# ng = 0
# print(calc(0))
from collections import Counter

CA = Counter(A)
keys = sorted(list(CA.keys()), reverse=True)

bunbo = 1
bunshi = 1
total = n
for key in keys:
    num = CA[key]
    while num:
        bunbo *= total
        total -= 1
        bunshi *= num
        num -= 1
print(bunbo // bunshi)