#include<iostream>
#include<fstream>
using namespace std;

int cmmdc(int a, int b){
    int c;
    while (b) {
        c = a % b;
        a = b;
        b = c;
    }
    return a;
}

int main(){
ifstream fin("fractii.in");
ofstream fout("fractii.out");
int n, i, nr;
fin>>n;
nr=n;
i=2;
for(i; n; i++){
if ()cmmdc(i, n)==1)
nr++;}
fout<<nr;
return 0;

}