#include <bits/stdc++.h>
using namespace std;
const int MOD = 1000000007;
const int MAXN = 50 + 10;
template <typename T>
inline void add(T& a, T b) {
  a += b;
  if (a >= MOD) a -= MOD;
}
int main() {
  static long long g[MAXN][MAXN];
  static long long f[MAXN][MAXN];
  static long long F[MAXN][MAXN];
  static long long inv[MAXN];
  ios::sync_with_stdio(0);
  int n, m;
  cin >> n >> m;
  inv[0] = inv[1] = 1;
  for (int i = 2; i <= n; ++i) inv[i] = inv[MOD % i] * (MOD - MOD / i) % MOD;
  f[0][1] = 1;
  for (int i = 1; i <= n; ++i) {
    for (int j = 1; j <= i + 1; ++j) {
      for (int p = 0; p <= i - 1; ++p) {
        for (int q = j; q <= p + 1; ++q)
          add(g[i][j], f[p][q] * f[i - 1 - p][j] % MOD);
        for (int q = j + 1; q <= i - p; ++q)
          add(g[i][j], f[p][j] * f[i - 1 - p][q] % MOD);
      }
      memset(F, 0, sizeof(F));
      for (int k = 0; k <= n; ++k) {
        for (int p = 1; p <= k + 1; ++p) {
          long long c = 1;
          for (int q = 1; k + q * i <= n; ++q) {
            c = c * (g[i][j] + q - 1) % MOD * inv[q] % MOD;
            add(F[k + q * i][p + q * j], f[k][p] * c % MOD);
          }
        }
      }
      for (int k = 0; k <= n; ++k)
        for (int p = 1; p <= k + 1; ++p) add(f[k][p], F[k][p]);
    }
  }
  cout << f[n][m] << endl;
}
