#include <iostream>
#include <iosfwd>
#include <iomanip>
#include <cstdio>
#include <cstring>
#include <cstdlib>
#include <ctime>
#include <cmath>
#include <cassert>
#include <cctype>
#include <climits>
#include <vector>
#include <bitset>
#include <set>
#include <queue>
#include <stack>
#include <map>
#include <deque>
#include <string>
#include <list>
#include <iterator>
#include <sstream>
#include <complex>
#include <fstream>
#include <functional>
#include <numeric>
#include <utility>
#include <algorithm>
#include <assert.h>
#include <unordered_map>
using namespace std;

typedef long long ll;
typedef unsigned long long ull;
typedef long double ld;
typedef vector <long long> vll;
typedef pair <long long, long long> pll;
typedef pair <int, int> pii;
typedef vector <int> vii;
typedef complex <double> Point;

#define csl ios_base::sync_with_stdio(false); cin.tie(NULL)
#define mp make_pair
#define fst first
#define snd second

long long t, n, m, u, v, q, k;
const int N = 1205;
const long long mod = 1e9 + 7;
const long long INF = 1LL << 61LL;
long long arr[N], brr[N];
string str, ss;

long long dp[N][N];
int R[N];
long long Cnk[N][N];
ll fact[N], ifact[N], inv[N];
void _pre() {
  fact[1] = fact[0] = 1; ifact[0] = ifact[1] = 1; inv[0] = inv[1] = 1;
  for (int i = 1; i < N; ++i) fact[i] = (fact[i - 1] * i) % mod;
  for (int i = 2; i < N; ++i) inv[i] = (((-(mod / i) * inv[mod % i]) % mod) + mod) % mod;
  for (int i = 2; i < N; ++i) ifact[i] = (ifact[i - 1] * inv[i]) % mod;
}
ll C(int n, int k) {
  if (k > n) return 0;
  if (n < 0 || k < 0) return 0;
  return (fact[n] * ((ifact[n - k] * ifact[k]) % mod)) % mod;
}
int main() {
  csl;
  cin >> n;
  for (int i = 1; i <= n; ++i) {
    cin >> arr[i];
  }
  R[n] = n;
  _pre();
  for (int i = 0; i <= n; ++i) {
    for (int j = 0; j <= n; ++j) Cnk[i][j] = C(i, j);
  }
  for (int i = n - 1; i >= 1; --i) {
    if (arr[i + 1] >= arr[i]) R[i] = R[i + 1];
    else R[i] = i;
  }
  for (int i = 1; i <= R[1]; ++i) {
    dp[i][i] = 1;
  }
  for (int i = 1; i <= n - 1; ++i) {
    for (int j = 1; j <= i; ++j) {
      if (dp[i][j] == 0) continue;
      //cout << i << " " << j << dp[i][j] << '\n';
      for (int k = 1; k <= j; ++k) {
        if (R[i + 1] - (i + 1) + 1 < k) break;
        dp[i + 1 + (k - 1)][k] = (dp[i + 1 + (k - 1)][k] + fact[k] * (1LL * (Cnk[j][k] * dp[i][j])% mod)) % mod;
      }
    }
  }
  int sol = 0;
  for (int i = 1; i <= n; ++i) {
    sol += dp[n][i];
    if (sol >= mod) sol -= mod;
  }
  cout << sol << '\n';
  return 0;
}