import sys
readline=sys.stdin.readline

N=int(readline())
A=list(map(int,readline().split()))
for i in range(N):
    if A[i]>=4:
        A[i]=3
cnt=[0]*4
for a in A:
    cnt[a]+=1
ans=0
for j in range(1,4):
    for i in range(1,j):
        for mex in range(1,4):
            if not mex in (i,j):
                break
        ans+=cnt[i]*cnt[j]*mex
for i in range(1,4):
    for mex in range(1,3):
        if mex!=i:
            break
    ans+=cnt[i]*(cnt[i]-1)//2*mex
print(ans)