#include <bits/stdc++.h>

using namespace std;
#define int long long
#define all(a) (a).begin(), (a).end()
#define ms(a,v) memset(a, v, sizeof(a))
#define sz(v) ((int)(v).size())
#define mp make_pair
#define pb push_back
#define prev biiiiirl_sai_de_casa_comi_pra_caralho
#define next trapezio_descendente
#define index eh_ele_que_nos_vai_buscar
#define left aqui_eh_37_anos_porra
#define R32 ({int32_t x; scanf("%d", &x); x;})
#define RL ({long long x; scanf("%lld", &x); x;})
#define RC ({char x; scanf(" %c", &x); x;})
#define RI RL
#define ff first
#define ss second
typedef pair<int, int> ii;
typedef vector<int> vi;
typedef vector<vi> vvi;
typedef vector<ii> vii;
typedef long long ll;

const int N = 1210;
const int MOD = (int)1e9+7;
int a[N];
int dp[N][N];
int bad_memo[N][N];

int n;
int C[N][N];
int fat[N];

int F(int x){
  if(x == 0) return 1;
  if(fat[x] != -1) return fat[x];
  return fat[x] = F(x-1)*x%MOD;
}

int nCr(int n, int r){
  if(r > n) return 0;
  if(r == 0 || r == n) return 1;
  if(C[n][r] != -1) return C[n][r];
  return C[n][r] = (nCr(n-1, r) + nCr(n-1, r-1))%MOD;
}

bool bad(int i, int mx){
  if(mx == 1) return false;
  if(bad_memo[i][mx] != -1) return bad_memo[i][mx];
  return bad_memo[i][mx] = !(a[i+mx-1] > a[i+mx-2] && !bad(i, mx-1));
}

int go(int i, int mx){
  if(i+mx > n) return 0;
  if(bad(i, mx)) return 0;
  if(i+mx == n) return 1;

  if(dp[i][mx] != -1) return dp[i][mx];
  int & res = dp[i][mx];
  res = 0;

  for(int j = 1; j <= mx; j++){
    res += go(i+mx, j)*nCr(mx, j)%MOD*F(j)%MOD;
    res %= MOD;
  }

  return res;
}

int32_t main(){
  memset(dp, -1, sizeof dp);
  memset(C, -1, sizeof C);
  memset(fat, -1, sizeof fat);
  memset(bad_memo, -1, sizeof bad_memo);

  n = RI;
  for(int i = 0; i < n; i++) a[i] = RI;

  int ans = 0;
  for(int i = 1; i <= n; i++){
    ans += go(0, i);
    ans %= MOD;
  }

  cout << ans << endl;
}