/*
Wed Jan  8 17:31:19 EST 1997
Wed Jan  8 17:38:12 EST 1997
*/


#include <stdio.h>
#include <stdlib.h>

#define N 100000
int *s;
int *ind;

int main()
{
	int n;
	int i,j;
	s=(int *)calloc(N, sizeof(int));
	ind=(int *)calloc(N, sizeof(int));
	
	s[0]=1;
	s[1]=1;
	s[2]=0;
	for (i=2;i<N;i++) {
		if ( s[i]==0 ) {
			for ( j=i+i;j<N;j+=i) {
				s[j]=1;
			}
		}
	}
	j=1;
	for (i=0;i<N;i++) {
		if (  !s[i] ) ind[j++]=i;
	}
	while(1==scanf(" %d",&n)) printf("%d\n",ind[n]);

	return 0;
	
}