#include <bits/stdc++.h>
using namespace std;
constexpr int mod = 1e9 + 7;
int dp[256][256][256];
int main() {
  int n;
  string s;
  cin >> n >> s;
  const int m = s.size();
  vector<vector<int>> match(m + 1, vector<int>(2));
  for (int i = 0; i < m; ++i) {
    for (int tl = 0; tl < 2; ++tl) {
      auto t = s.substr(0, i);
      t += tl == 0 ? '(' : ')';
      const int len = i + 1;
      string s1, s2;
      for (int j = 0; j < len; ++j) {
        s1 += s[j];
        s2 = t[i - j] + s2;
        if (s1 == s2) {
          match[i][tl] = j + 1;
        }
      }
    }
  }
  match[m][0] = match[m][1] = m;
  dp[0][0][0] = 1;
  for (int i = 0; i < 2 * n; ++i) {
    for (int j = 0; j <= m; ++j) {
      for (int k = 0; k < 2 * n; ++k) {
        (dp[i + 1][match[j][0]][k + 1] += dp[i][j][k]) %= mod;
        if (k != 0) {
          (dp[i + 1][match[j][1]][k - 1] += dp[i][j][k]) %= mod;
        }
      }
    }
  }
  cout << dp[2 * n][m][0] << endl;
}
