#include <bits/stdc++.h>
using ll = long long;
signed main() {
  std::ios::sync_with_stdio(false);
  std::cin.tie(0);
  ;
  int n;
  std::cin >> n;
  int t;
  std::cin >> t;
  ;
  std::vector<double> dp(n * (n + 1) / 2, 0);
  for (int i = 0; i < (t); i++) {
    dp[0] += 1;
    for (int j = 0; j < (n); j++) {
      for (int k = 0; k < (j + 1); k++) {
        int now = j * (j + 1) / 2 + k;
        if (dp[now] >= 1) {
          double diff = dp[now] - 1;
          dp[now] -= diff;
          if (j != n - 1) {
            dp[now + j + 1] += diff / 2;
            dp[now + j + 2] += diff / 2;
          }
        }
      }
    }
  }
  int cnt = 0;
  for (auto i : dp) {
    if (std::fabs(i - 1.0) < 0.001) ++cnt;
  }
  std::cout << (cnt);
  std::cout << "\n";
  ;
  return 0;
}
