#include <bits/stdc++.h>
using namespace std;
int main() {
  cin.sync_with_stdio(0);
  cin.tie(0);
  int N, K;
  cin >> N >> K;
  long long mod = 1000000007;
  vector<vector<long long> > A[2];
  for (int i = 0; i < 2; i++) A[i].resize(N + 1, vector<long long>(K + 1, 0));
  vector<vector<long long> > C(N + 1, vector<long long>(N + 1, 0));
  for (int i = 0; i <= N; i++) {
    C[i][0] = 1;
    for (int j = 1; j <= i; j++) {
      C[i][j] = (C[i - 1][j] + C[i - 1][j - 1]) % mod;
      if (C[i][j] < 0) C[i][j] += mod;
    }
  }
  A[0][0][0] = 1;
  for (int i = 1; i <= N; i++)
    for (int j = 0; j <= K; j++)
      for (int l = 0; 2 * l <= i - 1; l++) {
        long long x = ((l > 0) ? ((i - 1) * (i - 2) /
                                  ((2 * l == i - 1) ? 2 : 1) * C[i - 3][l - 1])
                               : max(1, i - 1)) %
                      mod;
        if (x < 0) x += mod;
        for (int k = 0; k <= j; k++) {
          long long y = (A[0][l][k] * A[0][i - 1 - l][j - k]) % mod;
          if (y < 0) y += mod;
          A[1][i][j] += (y * x) % mod;
        }
        A[1][i][j] %= mod;
        if (A[1][i][j] < 0) A[1][i][j] += mod;
        for (int k = 0; k < j; k++) {
          long long y =
              ((A[0][l][k] + A[1][l][k]) * A[1][i - 1 - l][j - 1 - k] +
               A[1][l][k] * A[0][i - 1 - l][j - 1 - k]) %
              mod;
          if (y < 0) y += mod;
          A[0][i][j] += (y * x) % mod;
        }
        A[0][i][j] %= mod;
        if (A[0][i][j] < 0) A[0][i][j] += mod;
      }
  cout << (A[0][N][K] + A[1][N][K]) % mod << "\n";
  return 0;
}
