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

public class Solution {
    public static void main(String[] args) {
        try (Scanner sc = new Scanner(System.in)) {
            int MaxN = sc.nextInt();
            long maxNumber = sc.nextLong();
            int bigNumbers = 0;
            ArrayList<Long[]> combinations = new ArrayList<>();
            for(int n = 0; n <= MaxN; n++) {
                Long[] list = new Long[n + 1];
                list[0] = list[n] = Long.valueOf(1);
                combinations.add(list);
            }
            for(int n = 1; n <= MaxN; n++) {
                for(int k = 1; k < n; k++) {
                    long sum = combinations.get(n - 1)[k - 1] + combinations.get(n - 1)[k];
                    if(sum > maxNumber) {
                        sum = maxNumber + 1;
                        bigNumbers++;
                    }
                    combinations.get(n)[k] = sum;
                }
            }
            System.out.println(bigNumbers);
        }
    }
}