K=int(input())
c=list(map(int,input().split()))
C=sum(c)
M=10**9+7
fa=[1,1]
fb=[1,1]
for i in range(2,C+1):
  fa+=[fa[-1]*i%M]
  fb+=[fb[-1]*(M//i)*fb[M%i]*fa[M%i-1]*(-1)%M]
g=[0]*(C+1)
for i in range(1,C+1):
  a=1
  for v in c:
    if v%i==0:
      a*=fb[v//i]
      a%=M
    else:
      a=0
  g[i]=a*fa[C//i]%M
from math import gcd
print(sum(g[C//gcd(i,C)] for i in range(1,C+1))*pow(C,M-2,M)%M)