#include <bits/stdc++.h>
using namespace std;
const int n = 12;
double ar[n][n];
int ans = 0;
int main() {
  int n, t;
  cin >> n >> t;
  ar[1][1] = t;
  for (int i = 1; i <= n; i++) {
    for (int j = 1; j <= i; j++) {
      if (ar[i][j] >= 1) {
        double ex = ar[i][j] - 1;
        ar[i + 1][j] += ex / 2;
        ar[i + 1][j + 1] += ex / 2;
        ar[i][j] = 1;
        ans++;
      }
    }
  }
  cout << ans;
}
