#include <bits/stdc++.h>
using namespace std;
double dp[11][11];
int main() {
  int n, t, ans;
  scanf("%d", &n);
  scanf("%d", &t);
  ans = 0;
  dp[0][0] = t;
  for (int i = 0; i < n; i++)
    for (int j = 0; j <= i; j++) {
      if (dp[i][j] >= 1) ans++;
      double temp = max((double)0, dp[i][j] - 1);
      dp[i + 1][j] += temp * 0.5;
      dp[i + 1][j + 1] += temp * 0.5;
    }
  printf("%d\n", ans);
  return 0;
}
