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

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

  ll N, M;
  cin >> N >> M;

  ll ans = 0;
  for(ll i = 1; i <= N; i++) {
    ll t = 0;
    if(M > i) { t += i * (M - i); }
    ll l = 1;
    while(l <= i) {
      ll q = i / l, r = i / q;
      if(M < l) { break; }
      if(M < r) { t += (i % l + i % M) * (M - l + 1) / 2; }
      else { t += (i % l + i % r) * (r - l + 1) / 2; }
      l = r + 1;
    }
    ans = max(ans, t);
  }

  cout << ans << "\n";
}