#include <bits/stdc++.h>
using namespace std;
double ar[11][11];
double n, k;
void fill(int x, int y, double p) {
  if (x > n || y > n) return;
  ar[x][y] += p;
  double left = ar[x][y] - 1.0;
  if (left > 0.0) {
    ar[x][y] = 1.0;
    fill(x + 1, y, p / 2);
    fill(x + 1, y + 1, p / 2);
  }
  return;
}
int main() {
  cin >> n >> k;
  memset(ar, 0, sizeof(ar));
  while (k--) {
    fill(1, 1, (double)1);
  }
  int ans = 0;
  for (int i = 1; i <= n; i++) {
    for (int j = 1; j <= n; j++)
      if (ar[i][j] >= 1.0) ans++;
  }
  cout << ans << endl;
}
