#include <bits/stdc++.h>
using namespace std;
int n, H;
long long f[40][40], ans;
int main() {
  scanf("%d%d", &n, &H);
  f[0][0] = 1;
  for (int i = 1; i <= n; i++)
    for (int h = 1; h <= i; h++)
      for (int j = 0; j < i; j++)
        if (f[j][h - 1]) {
          long long sum = 0;
          for (int k = 0; k < h - 1; k++) sum += f[i - j - 1][k];
          f[i][h] += f[j][h - 1] * sum * 2;
          f[i][h] += f[j][h - 1] * f[i - j - 1][h - 1];
        }
  for (int i = H; i <= n; i++) ans += f[n][i];
  printf("%lld\n", ans);
  return 0;
}
