#include <bits/stdc++.h>
using namespace std;
const int N = (int)1e5 + 17;
const int MX = (int)1e6 + 17;
const int MOD = (int)1e9 + 7;
const long long oo = LLONG_MAX;
const int INF = INT_MAX;
const long double Pi = 3.14159265358979323846264338327950288419716939937510;
const int di[4] = {-1, 0, 1, 0};
const int dj[4] = {0, 1, 0, -1};
inline long long IN() {
  long long x = 0, ch = getchar(), f = 1;
  while (!isdigit(ch) && (ch != '-') && (ch != EOF)) ch = getchar();
  if (ch == '-') {
    f = -1;
    ch = getchar();
  }
  while (isdigit(ch)) {
    x = (x << 1) + (x << 3) + ch - '0';
    ch = getchar();
  }
  return x * f;
}
inline void OUT(long long x) {
  if (x < 0) putchar('-'), x = -x;
  if (x >= 10)
    OUT(x / 10), putchar(x % 10 + '0');
  else
    putchar(x + '0');
}
void IOI2017() {}
int n, t, res;
double a[15][15], dp[15];
int main() {
  cin >> n >> t;
  a[1][1] = t;
  for (int i = 1; i <= n; i++) {
    for (int j = 1; j <= i; j++) {
      if (a[i][j] >= 1) {
        a[i + 1][j + 1] += (a[i][j] - 1) / 2;
        a[i + 1][j] += (a[i][j] - 1) / 2;
      }
      if (a[i][j] >= 1) res++;
    }
  }
  cout << res;
  return 0;
}
