#pragma GCC optimize("O3")
#include<bits/stdc++.h>
using namespace std;
#define rc(x) return cout<<x<<endl,0
#define pb push_back
#define dbg(x) cout << #x << '=' << x << '\n';
#define ll long long
#define sz size()
#define x first
#define y second
#define pi pair <int, int>
#define pii pair <pi, pi>
#define vi vector <int>
const ll mod = 1e9 + 7;
ll ans=1LL;
int n;

int gcd(int x, int y){
    if(x==1 || y==1) return 1;
    if(x==0) return y;
    if(y==0) return x;
    return gcd(y%x, x);
}

int32_t main(){
    ios_base :: sync_with_stdio(0); cin.tie(); cout.tie();
    ifstream cin("fractii.in");
    ofstream cout("fractii.out");
    cin>>n;
    for(int i=1; i<=n; i++){
        for(int j=i+1; j<=n; j++){
            if(gcd(i, j)==1) ans+=1LL*2;
        }
    } cout<<ans;
}