#include <bits/stdc++.h>
double rrr[12][12];
int main() {
  int n;
  double t, remain;
  scanf("%d%lf", &n, &t);
  rrr[1][1] = t;
  int rss = 0;
  for (int i = 1; i <= n; i++) {
    for (int j = 1; j <= i; j++) {
      if (rrr[i][j] >= 1.0) {
        rss++;
        remain = rrr[i][j] - 1;
        rrr[i + 1][j] += remain / 2;
        rrr[i + 1][j + 1] += remain / 2;
      }
    }
  }
  printf("%d", rss);
}
