#include <bits/stdc++.h>
using namespace std;
int main() {
  int n, h;
  cin >> n >> h;
  unsigned long long DP[37][37] = {};
  int L = 0, R = 0;
  DP[1][1] = 1;
  for (int i = 2; i <= n; i++) {
    for (int j = 2; j <= i; j++) {
      for (int k = 1; k <= i; k++) {
        L = k - 1, R = i - k;
        if (!(L && R)) {
          DP[i][j] += DP[L][j - 1] + DP[R][j - 1];
        }
        for (int x = 1; x < j - 1; x++) {
          DP[i][j] += DP[L][x] * DP[R][j - 1];
          DP[i][j] += DP[R][x] * DP[L][j - 1];
        }
        DP[i][j] += DP[L][j - 1] * DP[R][j - 1];
      }
    }
  }
  unsigned long long ans = 0;
  for (int i = h; i <= n; i++) {
    ans += DP[n][i];
  }
  cout << ans << "\n";
}
