use std::io::{ self, Write };
use std::str::FromStr;
use std::cmp::{ min, max };
use std::collections::{ BinaryHeap, VecDeque };

macro_rules! trace {
    ($var:expr) => ({
        let _ = writeln!(&mut std::io::stderr(), ">>> {} = {:?}", stringify!($var), $var);
    })
}
macro_rules! swap { ($a:expr, $b:expr) => ({ let t = $b; $b = $a; $a = t; }) }

fn prime_sieve(n: usize) -> Vec<bool> {
    let mut s = vec![true; n];
    s[0] = false; s[1] = false;
    for i in 2..n {
        if i * i > n { break }
        if s[i] {
            for k in 2..(n+i-1)/i { s[k * i] = false }
        }
    }
    s
}

fn main() {
    let mut sc = Scanner::new();
    let n: i32 = sc.cin();
    let L: i32 = sc.cin();
    let ps = prime_sieve((L / (n - 1) + 10) as usize);

    let mut ans: u64 = 0;
    for d in 2..(L/(n-1)+1) {
        if !ps[d as usize] { continue }
        // trace!(d);
        // trace!(max(0, L - d * (n-1) + 1));
        ans += max(0, L - d * (n-1) + 1) as u64;
    }
    println!("{}", ans);
}

#[allow(dead_code)]
struct Scanner { stdin: io::Stdin, buffer: VecDeque<String>, }
#[allow(dead_code)]
impl Scanner {
    fn new() -> Scanner { Scanner { stdin: io::stdin(), buffer: VecDeque::new() } }
    fn reserve(&mut self) {
        while self.buffer.len() == 0 {
            let mut line = String::new();
            let _ = self.stdin.read_line(&mut line);
            for w in line.split_whitespace() {
                self.buffer.push_back(String::from(w));
            }
        }
    }
    fn cin<T: FromStr>(&mut self) -> T {
        self.reserve();
        match self.buffer.pop_front().unwrap().parse::<T>() {
            Ok(a) => a,
            Err(_) => panic!("parse err")
        }
    }
    fn get_char(&mut self) -> char {
        self.reserve();
        let head = self.buffer[0].chars().nth(0).unwrap();
        let tail = String::from( &self.buffer[0][1..] );
        if tail.len()>0 { self.buffer[0]=tail } else { self.buffer.pop_front(); }
        head
    }
}