#include <map>
#include <set>
#include <list>
#include <cmath>
#include <ctime>
#include <deque>
#include <queue>
#include <stack>
#include <string>
#include <bitset>
#include <cstdio>
#include <limits>
#include <vector>
#include <climits>
#include <cstring>
#include <cstdlib>
#include <fstream>
#include <numeric>
#include <sstream>
#include <cassert>
#include <iomanip>
#include <iostream>
#include <algorithm>
#include <unordered_set>
#include <unordered_map>
 
#define pb push_back
#define mp make_pair
 
#define f first
#define s second
 
#define pii pair<int, int>
 
using namespace std;

typedef long long ll;
 
const int N = (int) 2e3 + 10;
const int MOD = (int) 1e9 + 7;

int n;
int a[N];

int dp[N][N];
int cnk[N][N];

int main() {
  #ifdef LOCAL
  freopen("in.txt", "r", stdin);
  //freopen("out", "w", stdout);
  #endif

  ios_base::sync_with_stdio(0);
  cin.tie(0);

  cnk[0][0] = 1;
  for (int i = 1; i < N; i++) {
    cnk[i][0] = cnk[i][i] = 1;
    for (int j = 1; j < i; j++)
      cnk[i][j] = (cnk[i - 1][j - 1] + cnk[i - 1][j]) % MOD;
  }

  cin >> n;
  for (int i = 1; i <= n; i++)
    cin >> a[i];

  reverse(a + 1, a + n + 1);

  dp[0][0] = 1;
  for (int i = 1; i <= n; i++) {
    bool good = 1;
    for (int j = i; j <= n; j++) {
      if (j > i)
        good &= (a[j] < a[j - 1]);
      if (!good)
        break;
      int clen = j - i + 1;
      int fact = 1;
      for (int plen = 0; plen <= clen; plen++) {
        int ank = cnk[clen][plen] * 1ll * fact % MOD;
        fact = fact * 1ll * (plen + 1) % MOD;
        dp[j][clen] = (dp[i - 1][plen] * 1ll * ank % MOD + dp[j][clen]) % MOD;
      }
    }
  }
  //cout<<dp[n][1]<<' '<<dp[n][2]<<' '<<dp[n][3]<<' '<<dp[n][4]<<endl;
  
  int ans = 0;
  for (int len = 0; len <= n; len++)
    ans = (ans + dp[n][len]) % MOD;
  cout << ans << endl;

  /*{1324}
  {12}{34}
  {}
  {1}{34}{2}
  {14}{3}{2}*/
  
  return 0;
}