import time
import sys
t1=time.clock()
f=open('in20_7.txt', 'r')
m=int(f.readline())
f.close()
l=2
k=1
p=[]
count=0
while count<m:
       i=2
       while i<=l/2:
              k=l%i
              i=i+1
              if k==0:
                     break
       if k!=0:
              back=""
              word=str(l)
              word=word.lower()
              for letter in word:
                     back=letter+back
              if word == back:
                     p.append(l)
                     count=count+1
       l=l+1
t2=time.clock()
t=t2-t1
z=str(p)
y=str(t)
ww=sys.getsizeof(t1)+sys.getsizeof(t2)+sys.getsizeof(word)+sys.getsizeof(back)+sys.getsizeof(i)+sys.getsizeof(m)+sys.getsizeof(z)+sys.getsizeof(k)+sys.getsizeof(count)+sys.getsizeof(t)+sys.getsizeof(l)+sys.getsizeof(p)
memory=str(ww+sys.getsizeof(ww))
out=open("out_17_20_7.txt","w")
out.write(z)
out.write("\nTime taken by program is "+y)
out.write("\nMemory used by program is "+memory+" bytes")
out.close()