#include<bits/stdc++.h>
using namespace std;
#define ll long long
signed main(){
	cin.tie(0);
	ios::sync_with_stdio(false);
	ll n;
	cin>>n;
	ll ans=0;
	for(ll i=1; i<=n; i++){
		ll k=min(n-i*(i-1)/2,i);
		if(k<=0) break;
		ans+=k*(1<<(i-1));
	}
	cout<<ans;
	return 0;
}