MOD = 10 ** 9 + 7
L = int(input())
ans = 1
for i in range(L):
    p, e = map(int, input().split())
    tmp = pow(p, e + 2, MOD)
    tmp -= (p - 1) * e + 2 * p - 1
    tmp *= pow(pow(p - 1, 2), -1, MOD)
    tmp %= MOD
    ans *= tmp
    ans %= MOD
print(ans)