#include<bits/stdc++.h>
using namespace std;
#include <atcoder/all>
using namespace atcoder;
using mint=modint998244353; //1000000007;
using ll=long long;
using pp=pair<int,int>;
#define sr string 
#define vc vector
#define fi first
#define se second
#define rep(i,n) for(int i=0;i<(int)n;i++)
#define pb push_back
#define all(v) v.begin(),v.end()
#define pque priority_queue
#define bpc(a) __builtin_popcount(a)
int main(){
  int n,m;cin>>n>>m;
  vc<ll>v(n+1,0);
  for(ll i=1;i<=m;i++)for(ll j=i;j<=n;j+=i)v[j]+=i;
  ll ans=0,now=0;
  for(ll i=1;i<=n;i++){
    now+=m;
    now-=v[i];
    ans=max(ans,now);
  }
  cout<<ans;
}