#include<bits/stdc++.h>
using namespace std;
map<long long, long long> dp;
int main()
{
int n,i;
dp[1]=1;
for(i=2;i<=1000000000;++i)
if(!dp[i])
for(int j=i+i;j<=1000000000;j+=i)
dp[i]=1;
i=2;
while(n){
if(!dp[i])--n;
if(n>0)++i;
}
cout<<i<<'\n';
return 0;
}