#include <bits/stdc++.h>
using namespace std;
const int N = 123;
long double dp[N][N];
int main() {
  int n, t;
  cin >> n >> t;
  dp[1][1] = t;
  int ans = 0;
  for (int i = 1; i < n; i++) {
    for (int j = 1; j <= i; j++)
      if (dp[i][j] + 1e-6 >= 1) {
        ans++;
        dp[i + 1][j] += max((long double)0, (dp[i][j] - 1) / 2);
        dp[i + 1][j + 1] += max((long double)0, (dp[i][j] - 1) / 2);
      }
  }
  for (int i = 1; i <= n; i++) ans += (dp[n][i] + 1e-6 >= 1);
  cout << ans << endl;
}
