import sys
from math import gcd
sys.setrecursionlimit(10**7)
def I(): return int(sys.stdin.readline().rstrip())
def MI(): return map(int,sys.stdin.readline().rstrip().split())
def LI(): return list(map(int,sys.stdin.readline().rstrip().split()))
def LI2(): return list(map(int,sys.stdin.readline().rstrip()))
def S(): return sys.stdin.readline().rstrip()
def LS(): return list(sys.stdin.readline().rstrip().split())
def LS2(): return list(sys.stdin.readline().rstrip())


K = I()
C = LI()
N = sum(C)
mod = 10**9+7

g = N  # g = gcd(N,C1,…,CK)
for c in C:
    g = gcd(g,c)

div = []  # gの約数
for i in range(1,g+1):
    if g % i == 0:
        div.append(i)

fac = [1]
for i in range(1,N+1):
    fac.append((fac[-1]*i) % mod)

fac_inv = [0]*(N+1)
a = pow(fac[-1],mod-2,mod)
for i in range(N,-1,-1):
    fac_inv[i] = a
    a *= i
    a %= mod


def f(n,M):
    # f(n,M) = n!/(m1!*m2!*…) (M = [m1,m2,…])
    res = fac[n]
    for m in M:
        res *= fac_inv[m]
        res %= mod
    return res


def phi(n):
    if n == 1:
        return 1
    res = n
    for i in range(2,int(n**.5)+1):
        if n % i == 0:
            res -= res//i
            while n % i == 0:
                n //= i
            if n == 1:  # 時間短縮
                break
    else:
        res -= res//n
    return res


ans = 0
for d in div:
    ans += phi(d)*f(N//d,[c//d for c in C])
    ans %= mod

ans *= pow(N,mod-2,mod)
ans %= mod
print(ans)