28237
 13190
 39914
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 8554
 61106
 67448
 39004
 22308
 16054
 71468
 60501
 100
 300
 59632
 90783
 5611
 1000
 69475
 69753
 10
 5
 582
 8
 36961
 5071
 20
 53213
 92775
 28738
 100000
 92280
 37944
 9
 2627
 7
 3

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#include<bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
#include <functional>
#include <cassert>
using namespace std;
using namespace __gnu_pbds;
typedef tree<long long int, null_type, less_equal<long long int>, rb_tree_tag, tree_order_statistics_node_update> ordered_set; //less_equal
#define ll long long int
#define ull unsigned long long int
#define mod 1000000007
#define pb push_back
#define mp make_pair
#define pp pair<int, int>
#define ppl pair<ll, ll>
#define loop(i,s,n) for(int i=s ; i<=n ; i++)
#define loopl(i,s,n) for(ll i=s ; i<=n ; i++)
#define loopr(i,e,s) for(int i=e; i>=s ; i--)
#define speedUp ios_base::sync_with_stdio(false); cin.tie(0); cout.tie(0)

int main(){
    //ab_gupta
    speedUp;
    int n;cin>>n;
    ll ans=0;
    loop(i,2,n) ans+=((n/i)*((n/i)+1))*2-4;
    cout<<ans;
    return 0;
}//

