#include <bits/stdc++.h>
using namespace std;
double amount[12][12];
int cnt;
int n;
void addpani(double totpani) {
  cnt = 0;
  double currpani = totpani;
  amount[1][1] = totpani;
  for (int i = 1; i <= n; i++) {
    for (int j = 1; j <= i; j++) {
      if (amount[i][j] >= 1) {
        amount[i + 1][j] += (amount[i][j] - 1) / 2;
        amount[i + 1][j + 1] += (amount[i][j] - 1) / 2;
        amount[i][j] = 1;
        cnt++;
      }
    }
  }
}
int main() {
  int T;
  cin >> n;
  cin >> T;
  addpani(T);
  cout << cnt;
}
