#include <bits/stdc++.h>
using namespace std;

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

    int N,M; cin >> N >> M;
    long long answer = 0;
    for(int i=1; i<=N; i++){
        long long now = 1LL*i*M;
        long long k;
        for(k=1; k*k<=N&&k<=M; k++) now -= i/k*k;
        while(i/k && k<=M){
            long long dec = i/k;
            long long maxk = i/dec;
            now -= dec*(maxk*(maxk+1)/2-(k-1)*k/2);
            k = maxk+1;
        }
        answer = max(answer,now);
    }
    cout << answer << endl;
}