N = int(input())
A = sorted([int(i) for i in input().split()])

sum = 0
for i in range(N):
	if A[i] == 1:
		for j in range(i+1,N):
			if A[j] == 1:
				sum += 2
			elif A[j] == 2:
				sum += 3
			else:
				sum = sum + 2*((N-1)-j+1)
				break
	elif A[i] == 2:
		for j in range(i+1,N):
			if A[j] == 2:
				sum += 1
			else:
				sum = sum + 2*((N-1)-j+1)
				break
	else:
		sum = sum + int(((N-1)-i+1)*(N-1)/2)
		break
print(sum)