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from math import gcd


def reduced(f):
    a, b = f
    g = gcd(a, b)
    return (a // g, b // g)


def add(x, y):
    xa, xb = x
    ya, yb = y
    return reduced((xa * yb + ya * xb, xb * yb))


def mult(x, y):
    xa, xb = x
    ya, yb = y
    return reduced((xa * ya, xb * yb))


def lcm(a, b):
    return a // gcd(a, b) * b


n = int(input())
F = [(0, 1) for _ in range(n + 1)]
F[1] = (1, 1)
ans = 1
for i in range(1, n + 1):
    lst = input().split(' ')
    l = int(lst[0])
    if l != 0:
        f = (1, l)
        ff = mult(F[i], f)
        for j in range(1, l + 1):
            x = int(lst[j])
            F[x] = add(F[x], ff)
        _, ffb = ff
        ans = lcm(ans, ffb)
print(ans)