import java.util.Arrays;
import java.util.Scanner;

public class Main {
	public static void main(String[] args) {
		solver();
	}

	static void solver() {
		Scanner sc = new Scanner(System.in);
		int n = sc.nextInt();
		int l = sc.nextInt();
		if(l/(n-1)>=2){
			boolean[] isPrime = isPrimeArray(l / (n - 1));
			long ans = 0;
			for (int i = 2; i <= l / (n - 1); i++) {
				if (isPrime[i]) {
					ans += l - (n - 1) * i + 1;
				}
			}
			System.out.println(ans);

		}else{
			System.out.println(0);
			return;
		}

	}

	static int count = 0;

	static boolean[] isPrimeArray(int max) {
		boolean[] isPrime = new boolean[max + 1];
		Arrays.fill(isPrime, true);
		isPrime[0] = isPrime[1] = false;
		for (int i = 2; i * i <= max; i++) {
			if (isPrime[i]) {
				for (int j = 2; j * i <= max; j++) {
					isPrime[j * i] = false;
				}
			}
		}
		return isPrime;
	}
}