#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef unsigned long long ull;
typedef pair<ll,ll> P;
#define fi first
#define se second
#define mkp make_pair
#define pb emplace_back
#define popcnt __builtin_popcountll
const ll mod = 998244353;
inline ll read(){
	ll x=0, f=1; char ch=getchar();
	while(ch<'0' || ch>'9') { if(ch=='-') f=-1; ch=getchar(); }
	while(ch>='0' && ch<='9') x=x*10+ch-'0', ch=getchar();
	return x*f;
}
inline int lg2(int x){ return 31^__builtin_clz(x); }
inline ll lg2(ll x){ return 63^__builtin_clzll(x); }
inline void addmod(int &x){ if(x >= mod) x -= mod; }
inline void addmod(ll &x){ if(x >= mod) x -= mod; }
inline ll qpow(ll a,ll b){
	ll ans=1, base=a;
	while(b){
		if(b&1) ans=ans*base%mod;
		base=base*base%mod; b>>=1;
	}
	return ans;
}
inline ll INV(ll x){ return qpow(x, mod-2); };
const int n = 100000;
int m,f[100005],id[100005],low[100005],vis[100005],mu[100005];
vector<int>v[100005],t[100005],fac[100005];

void init(){
	mu[1]=1;
	for(int i=1;i<=n;i++){
		for(int j=i;j<=n;j+=i){
			fac[j].pb(i);
			if(j>i) mu[j]-=mu[i];
		}
	}
	for(int i=2;i<=n;i++){
		if(!vis[i]){
			for(int j=i;j<=n;j+=i){
				vis[j]=1;
				if(!low[j]) low[j]=i;
				v[j].pb(i);
			}
		}
	}
	for(int i=1;i<=n;i++){
		id[i]=1;
		for(auto w: v[i]) id[i]*=w;
		t[id[i]].pb(i);
	}
}

void procedure(){
	init();
	m=read();
	ll cnt = 0;
	for(int b=2;b<=m;b++)
		for(auto w: fac[id[b]])
			for(auto s: t[w]){
				// s|a, a<b
				// s|n, gcd(n/s,id[b])=1

				int up=m/s, cc = 0;
				for(auto fk: fac[id[b]]){
					cc += mu[fk] * (up / fk);
				}
				cnt += 1ll * ((b-1)/s) * cc;
			}
	printf("%lld\n", cnt);
}

int main(){
	#ifdef LOCAL
		assert(freopen("input.txt","r",stdin));
		assert(freopen("output.txt","w",stdout));
	#endif
	ll T=1;
	// math_init();
	// NTT::init();
	while(T--) procedure();
	return 0;
}