MOD = 10 ** 9 + 7

l = int(input())
ans = 1
for _ in range(l):
    p, e = map(int, input().split())
    e += 1
    s = pow(p, e, MOD) - e
    s %= MOD
    inv = pow(p - 1, MOD - 2, MOD)
    s += p * (pow(p, e - 1, MOD) - 1) * inv
    s %= MOD
    ans *= s * inv % MOD
    ans %= MOD

print(ans)