#include <bits/stdc++.h>
using namespace std;
const int N = 55;
int n, m;
long long dp[N][N], s[N][N];
int main() {
  int i, j, k;
  scanf("%d%d", &n, &m);
  dp[0][0] = 1;
  for (j = 0; j <= n; ++j) s[0][j] = 1;
  dp[1][1] = 1;
  for (j = 1; j <= n; ++j) s[1][j] = 1;
  for (i = 2; i <= n; ++i) {
    for (j = 1; j <= i; ++j)
      for (k = 0; k < i; ++k) {
        dp[i][j] += s[k][j - 1] * s[i - 1 - k][j - 1];
        if (j >= 2) dp[i][j] -= s[k][j - 2] * s[i - 1 - k][j - 2];
      }
    for (j = 1; j <= n; ++j) s[i][j] = s[i][j - 1] + dp[i][j];
  }
  printf("%lld\n", s[n][n] - s[n][m - 1]);
  return 0;
}
