import java.util.ArrayList;
import java.util.Scanner;

public class Main {
	public static void main(String[] args) {
		Scanner scan = new Scanner(System.in);
		int N = scan.nextInt();
		int L = scan.nextInt();
		scan.close();
		int max = L / (N -1);
		ArrayList<Integer> list = new ArrayList<Integer>();
		for(int i = 2; i <= max; i++) {
			if(isPrime(i)) {
				list.add(i);
			}
		}
		long cnt = 0;
		for(int i = 0; i < list.size(); i++) {
			if(L - (N - 1) * list.get(i) >= 0) {
				cnt += L - (N - 1) * list.get(i) + 1;
			}
		}
		System.out.println(cnt);
	}
	static boolean isPrime(int n) {
		if(n == 2) {
			return true;
		}
		if(n % 2 == 0) {
			return false;
		}
        for(int i = 3; i <= (int)Math.sqrt(n); i+=2){
            if(n % i == 0) {
                return false;
            }
        }
        return true;
    }
}