#include <bits/stdc++.h>
//#include <atcoder/modint>

using namespace std;
//using namespace atcoder;
using ll = long long;
//using mint = modint998244353;

int main(){
    cin.tie(nullptr);
    ios_base::sync_with_stdio(false);

    ll N, M, x, l, r;
    cin >> N >> M;
    //v(x) = sum(i=1 to M) (x/i)*i
    vector<ll> v(N+2);
    for (int i=1; i<=M; i++){
        x = N/i;
        for (int j=1; j<=x; j++){
            //j*i~(j+1)*i-1にj*iを足す。
            l = j*i;
            r = min((j+1)*i-1, (int)N);
            v[r+1] -= j*i;
            v[l] += j*i;
        }
    }
    ll ans=0;
    for (int i=1; i<=N; i++) v[i] += v[i-1];
    for (int i=1; i<=N; i++){
        ans = max(ans, M*i-v[i]);
    }
    cout << ans << endl;

    return 0;
}