import sys
from time import time
from math import sqrt
with open('test_file.txt', 'w', encoding='utf-8') as f:
    sys.stdout = f
    n= int(input())
    start_time = time()
    numb = {k for k in range(2,n+1)}
    for k in range (2, int(sqrt(n))+2):
            if  k not in numb:
                continue
            else:
                for r in range (2*k, n+1,k):
                    numb.discard(r)
    print(numb)
    print('--- %s seconds ---' % (time() - start_time))