import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;

class Main {
	public static void main(String[] args) throws IOException {
		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
		String[] str = br.readLine().split(" ");
		br.close();
		int num = Integer.parseInt(str[0]) - 1;
		int len = Integer.parseInt(str[1]);

		long count = 0;

		int n = len / num;
		if(n==0){
			System.out.println(0);
			return;
		}

		int[] prime = new int[n];

		int i, j,primeNum;

		prime[0] = 0;
		for (i = 1; i < n; i++) {
			prime[i] = 1;
		}
		for (i = 1; i < n; i++) {
			if (prime[i] == 1) {
				primeNum = i + 1;

				for(j=i+primeNum;j<n;j+=primeNum){
					prime[j]=0;
				}
			}
		}

		for(i=1;i<n;i++){
			if(prime[i]==1){
				primeNum=i+1;
				count+=len-num*(i+1)+1;
			}
		}

		System.out.println(count);
	}
}