#include<stdio.h>

int main(){
	long n,i;
	int fi = 4; int th = 2;
	int res = 0;
	scanf("%ld",&n);
	for(i = 1; i <= n; i++){
		if(i%15 == 0){
			res+=fi;
			continue;
		}else if(i%5 == 0 || i%3 == 0){
			res+=th;
		}
	}
	printf("%d",res);
	return 0;
}