test

#include<iostream>
#include<cmath>
#include<cstring>
#include<vector>
#include<array>
#include<memory>
//#include<list>
//#include<stack>
//#include<queue>
//#include<map>
//#include<set>
//#include<cstdio>
//#include<cstdlib>
#include<algorithm>
using namespace std;
int f(int n){
    for(int i = 1; ; i++){
        if(n % i == 0) continue;
        else return i;
    }
    return -1;
}
int s(int n){
    int sum = 0;
    for(int i = 1; i <= n; i++){
        cout << "f[" << i << "]" << "=" << f(i) << endl;
        sum += f(i);
    }
    return sum;
}
int main(){
    //freopen("C:\\Users\\Ambition\\Desktop\\in.txt","r",stdin);
    int n;
    while(cin >> n){
        cout << s(n) << endl;
    }
    return 0;
}