def foo():
    list = set()
    for i in range(300):
        for j in range(2, i-1):
            print('{} / {}'.format(i, j))
            if not i % j:
                break
            list.add(i)
    print(list)
foo()

def foo():
    list = set()
    for i in range(300):
        flag = True
        for j in range(2, 1 + int(math.sqrt(i))):
            if not i % j:
                flag = False
                break
        if flag:
            list.add(i)
    print(list)

foo()

def foo():
    list = set()
    for i in range(300):
        for j in range(2, 1 + int(math.sqrt(i))):
            if not i % j:
                break
        else:
            list.add(i)
    print(list)

foo()

def isPrime(n):
  for j in range(3, int(n**0.5)+1):
    if n%j==0:
      return 0
  return 1
def search(n):
  primes = [2]
  i = 3
  while len(primes)<n:
    if isPrime(i) == 1:
      primes.append(i)
    i+=2
  return primes