#include <iostream> using namespace std; int main() { int i,j,n,a[100001]; j=1; i=3; while (scanf("%d",&n)!=EOF) { while (j<=n) { if (i%3==0 or i%5==0) a[j++]=i; i++; } printf("%d\n",a[n]); j=1; i=3; } return 0; }