#include <bits/stdc++.h>
using namespace std;
unsigned long long dp[40][40], n, h;
int main() {
  dp[0][0] = dp[1][0] = dp[1][1] = 1;
  cin >> n >> h;
  for (unsigned long long i = 2; i <= n; i++) {
    for (unsigned long long j = 1; j <= i; j++)
      for (unsigned long long u = 0; u < i; u++)
        dp[i][j] += (dp[u][j - 1] * dp[i - u - 1][0]) +
                    (dp[u][0] * dp[i - u - 1][j - 1]) -
                    (dp[u][j - 1] * dp[i - u - 1][j - 1]);
    dp[i][0] = dp[i][1];
  }
  cout << dp[n][h];
}
