#include <bits/stdc++.h>
using namespace std;
double a[15][15];
int n;
void Pour(int i, int j, double flow) {
  if (i == n + 1) return;
  if (a[i][j] < 1)
    a[i][j] = a[i][j] + flow;
  else {
    Pour(i + 1, j, flow / 2);
    Pour(i + 1, j + 1, flow / 2);
  }
}
int main() {
  int i, j, t, s, cnt = 0;
  cin >> n >> t;
  for (s = 1; s <= t; s++) Pour(1, 1, 1);
  for (i = 1; i <= n; i++)
    for (j = 1; j <= i; j++)
      if (a[i][j] >= 1) cnt++;
  cout << cnt << endl;
  return 0;
}
