#include <bits/stdc++.h>
using namespace std;
int main() {
  int N, T;
  cin >> N >> T;
  if (T == 0) {
    cout << 0 << endl;
    return 0;
  }
  int tot = 1;
  long double c[15][15];
  c[1][1] = T;
  long double eps = 1e-9;
  for (int n = 2; n <= N; n++) {
    if (c[n - 1][1] - 1.0 > -eps) {
      c[n][1] = (c[n - 1][1] - 1.0) / 2.0;
      tot += c[n][1] - 1.0 > -eps;
    }
    for (int j = 2; j < n; j++) {
      c[n][j] = 0.0;
      if (c[n - 1][j - 1] - 1.0 > -eps) {
        c[n][j] = (c[n - 1][j - 1] - 1.0) / 2.0;
      }
      if (c[n - 1][j] - 1.0 > -eps) {
        c[n][j] += (c[n - 1][j] - 1.0) / 2.0;
      }
      if (c[n][j] - 1.0 > -eps) {
        tot++;
      }
    }
    if (c[n - 1][n - 1] - 1.0 > -eps) {
      c[n][n] = (c[n - 1][n - 1] - 1.0) / 2.0;
      tot += c[n][n] - 1.0 > -eps;
    }
  }
  cout << tot << endl;
  return 0;
}
