def ss(i): for j in range (1,i): if i%j==0: return False return True def hw(i): x=i k=0 while x!=0: k=k*10+x%10 x=x//10 if k==i: return True else: return False n=int(input()) for i in range(2,n+1): if ss(i) and hw(i): print(i)