#include <bits/stdc++.h>
using namespace std;
double dp[15][15];
int main() {
  int n, t;
  int ans = 1;
  scanf("%d%d", &n, &t);
  dp[1][1] = t;
  for (int i = 2; i <= n; i++) {
    for (int j = 1; j <= i; j++) {
      if (dp[i - 1][j - 1] > 1) dp[i][j] += (dp[i - 1][j - 1] - 1) / 2;
      if (dp[i - 1][j] > 1) dp[i][j] += (dp[i - 1][j] - 1) / 2;
      if (dp[i][j] >= 1) ans++;
    }
  }
  if (t == 0) ans = 0;
  printf("%d\n", ans);
}
