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#!/usr/bin/python3

from math import gcd

#def gcd(a, b):
#  assert(0 <= a)
#  assert(0 <= b)
#  assert(0 < a or 0 < b)
#  if a == 0:
#    return b
#  return gcd(b % a, a)

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

def skroc(u):
  (a, b) = u
  assert b != 0
  g = gcd(a, b)
  return (a // g, b // g)

def dodaj(u1, u2):
  (u1a, u1b) = u1
  (u2a, u2b) = u2
  return skroc((u1a * u2b + u2a * u1b, u1b * u2b))

def podziel(u, co):
  (a, b) = u
  return skroc((a, b * co))

n = int(input())

ile = [(0, 1) for i in range(n + 1)]
stopy = [0 for i in range(n + 1)]

ile[1] = (1, 1)

for i in range(1, n + 1):
  ciag = [int(s) for s in input().split()]
  assert len(ciag) >= 1
  l = ciag[0]
  stopy[i] = l
  ciag = ciag[1:]
  assert len(ciag) == l
  for j in ciag:
    assert i < j <= n
    ile[j] = dodaj(ile[j], podziel(ile[i], l))

out = 1
for i in range(1, n + 1):
  (a, b) = ile[i]
  #print(i, a, b, ile[i], stopy[i])
  if a > 0:
    if stopy[i] == 0:
      out = nww(out, b)
    else:
      out = nww(out, stopy[i] * b // gcd(stopy[i] * b, a))

print(out)