#include <bits/stdc++.h>
int n, t;
double arr[11][11];
int squ(int x) {
  int ret = 1;
  for (int i = 1; i < x; i++) {
    ret *= 2;
  }
  return ret;
}
int main() {
  int i, j, flag, sol = 0;
  scanf("%d %d", &n, &t);
  arr[1][1] = (double)t;
  for (i = 1; i <= n; i++) {
    flag = 0;
    for (j = 1; j <= i; j++) {
      if (arr[i][j] > 1) {
        arr[i][j] -= 1;
        sol++;
        arr[i + 1][j] += arr[i][j] / 2;
        arr[i + 1][j + 1] += arr[i][j] / 2;
        flag = 1;
      } else if (arr[i][j] == 1)
        sol++;
    }
    if (flag == 0) break;
  }
  printf("%d\n", sol);
  return 0;
}
