N=int(input())
A=list(map(int,input().split()))
from collections import Counter
one,two=0,0
other=0
l=[[0]*3 for i in range(N+1)]
for i in range(N):
    l[i+1][0]=l[i][0]
    l[i+1][2]=l[i][2]
    l[i+1][1]=l[i][1]
    if A[i]==1:
        l[i+1][0]+=1
    elif A[i]==2:
        l[i+1][1]+=1
    else:
        l[i+1][2]+=1
ans=0
for i,j in enumerate(A):
    tmp_l=l[i]
    if j==1:
        ans+=tmp_l[0]*2+tmp_l[1]*3+tmp_l[2]*2
    elif j==2:
        ans+=tmp_l[0]*3+tmp_l[1]+tmp_l[2]
    else:
        ans+=tmp_l[0]*2+tmp_l[1]+tmp_l[2]
print(ans)