#include <stdio.h>
int main() {
  unsigned long long N;
  scanf("%llu",&N);
  unsigned long long len=0;
  for(unsigned long long i=1;i<=N;i++) {
    if( !(i%15) ) len+=4;
    else if( !(i%3)||!(i%5) ) len+=2;
  }
  printf("%llu\n",len);
  return 0;
}