#![allow(non_snake_case, unused_must_use, unused_imports)]
use std::io::{self, prelude::*};

fn main() {
    let (stdin, stdout) = (io::read_to_string(io::stdin()).unwrap(), io::stdout());
    let (mut stdin, mut buffer) = (stdin.split_whitespace(), io::BufWriter::new(stdout.lock()));

    macro_rules! input {
        ($t: tt, $n: expr) => {
            (0..$n).map(|_| input!($t)).collect::<Vec<_>>()
        };
        (Chars) => {
            input!(String).chars().collect::<Vec<_>>()
        };
        (Usize1) => {
            stdin.next().unwrap().parse::<usize>().unwrap() - 1
        };
        ($t: ty) => {
            stdin.next().unwrap().parse::<$t>().unwrap()
        };
    }

    let A = input!(u128);
    let B = input!(u128);

    let f = |x| x * x * x - x * x + x + 1;

    let ans = (A..=B).filter(|&x| is_prime(x)).map(|x| f(x)).sum::<u128>();
    writeln!(buffer, "{}", ans);
}

fn is_prime(x: u128) -> bool {
    if x == 1 {
        return false;
    }

    for i in 2..x {
        if x % i == 0 {
            return false;
        }
    }

    return true;
}