#include <bits/stdc++.h>
using namespace std;
int main() {
  double arr[12][12] = {0.0};
  int n, t, ans = 0;
  scanf("%d %d", &n, &t);
  arr[1][1] = (double)t;
  for (int i = 1; i <= n; i++)
    for (int j = 1; j <= i; j++)
      if (arr[i][j] >= 1.0) {
        ans++;
        arr[i + 1][j] += (arr[i][j] - 1.0) / 2;
        arr[i + 1][j + 1] += (arr[i][j] - 1.0) / 2;
      }
  printf("%d\n", ans);
  return 0;
}
