#include <bits/stdc++.h>
using namespace std;
const double eps = 1e-10;
const int maxt = 10000 + 50;
int n;
int t;
double a[50][maxt];
int main() {
  cin >> n >> t;
  a[1][1] = 1.0 * t;
  int res = 0;
  for (int i = 1; i <= n; i++) {
    for (int j = 1; j <= i; j++) {
      if (a[i][j] > 1.0) {
        res++;
        a[i + 1][j] += 0.5 * (a[i][j] - 1.0);
        a[i + 1][j + 1] += 0.5 * (a[i][j] - 1.0);
        a[i][j] -= a[i][j] - 1.0;
      } else if (abs(a[i][j] - 1.0) < eps)
        res++;
    }
  }
  printf("%d\n", res);
  return 0;
}
