import java.util.*;

public class Main {
	public static void main (String[] args) {
    	Scanner sc = new Scanner(System.in);
    	int n = sc.nextInt();
    	int length = sc.nextInt();
    	ArrayList<Integer> primes = new ArrayList<>();
    	long ans = 0;
    	for (int i = 2; i * (n - 1) <= length; i++) {
    	    if (isPrime(i, primes)) {
    	        primes.add(i);
    	        ans += length - i * (n - 1) + 1;
    	    }
    	}
        System.out.println(ans);
	}
	
	static boolean isPrime(int x, ArrayList<Integer> primes) {
	    for (int y : primes) {
	        if (y * y > x) {
	            break;
	        }
	        if (x % y == 0) {
	            return false;
	        }
	    }
	    return true;
	}
}