#include <bits/stdc++.h>
using namespace std;
double s[11][11];
int sum, a, b;
int main() {
  scanf("%d %d", &a, &b);
  s[1][1] = b;
  for (int i = 1; i <= a; i++)
    for (int j = 1; j <= i; j++)
      if (s[i][j] >= 1) {
        s[i + 1][j + 1] += (s[i][j] - 1) / 2;
        s[i + 1][j] += (s[i][j] - 1) / 2;
        s[i][j] = 1;
        sum++;
      }
  printf("%d\n", sum);
  return 0;
}
