use std::cmp;

fn calc(x: i64, m: i64) -> i64 {
    let mut ans = x * m;

    let mut ind = 1;
    while ind <= m {
        let k = x / ind;
        if k == 0 {
            break;
        }
        let max_ind = x / k;

        let max_ind = cmp::min(max_ind, m);

        ans -= (ind + max_ind) * (max_ind - ind + 1) * k / 2;
        ind = max_ind + 1;
    }

    ans
}

fn main() {
    let mut input = String::new();
    std::io::stdin().read_line(&mut input).unwrap();
    let parts: Vec<i64> = input
        .trim()
        .split_whitespace()
        .map(|s| s.parse().unwrap())
        .collect();
    let n = parts[0];
    let m = parts[1];

    let mut ans = 0;

    for i in 0..=n {
        ans = cmp::max(ans, calc(i, m));
    }

    println!("{}", ans);
}