#include <bits/stdc++.h>
#define LL long long
#define ABS(a) (((a) > 0) ? (a) : (-(a)))
#define FOR(i,n) for(int i=0;i<(n);++i)
#define FORIT(it,c) for(__typeof((c).begin()) it=(c).begin();it!=(c).end();it++)
#define all(o) (o).begin(), (o).end()
#define pb push_back
#define mp make_pair
#define mset(m,v) memset(m,v,sizeof(m))
#define INF 0x3f3f3f3f
#define INFL 0x3f3f3f3f3f3f3f3fLL
#define MOD 1000000007
using namespace std;
typedef vector<int> vi;
typedef pair<int,int> pii;
template<typename T> ostream& operator<<(ostream& s, vector<T>& v)
{ s << '{'; for (int i = 0 ; i < v.size(); ++i) s << (i ? "," : "") << v[i]; return s << '}'; }
template<typename S, typename T> ostream& operator<<(ostream &s, pair<S,T>& p)
{ return s << "(" << p.first << "," << p.second << ")"; }

int N;
vi A;
LL pdp[1205][1205];
LL dp[1205][1205];

// number of ways if we're at step n, max layer size is m
LL f(int n, int m){
  LL &ans = dp[n][m];
  if(ans != -1){
    return ans;
  }

  // Trivial cases
  if(m == 1){
    ans = 1;
    return ans;
  }

  if(n == N){
    ans = 1;
    return ans;
  }

  ans = 0;
  for(int m2 = 1; m2 <= m; m2++){
    // can't do it if past end of string
    if(n + m2 > N) break;

    // can't do it if A[m2] decreasing
    if(m2 > 1 && A[n + m2 - 1] < A[n + m2 - 2]) break;

    LL d = f(n + m2, m2);
    if(n == 0){
      ans += d;
    }
    else{
      ans = (ans + d * pdp[m][m2]) % MOD;
    }
  }

  //cout << n << " " << m << " " << ans << endl;
  return ans;
}

// 869171677
int main(){
  FOR(i, 1205) FOR(j, 1205) dp[i][j] = -1;
  FOR(i, 1205) FOR(j, 1205) pdp[i][j] = -1;

  // optimization: calculate perms
  FOR(i, 1201){
    FOR(j, i+1){
      if(j == 0){
        pdp[i][j] = 1;
      }
      else{
        pdp[i][j] = (i * pdp[i-1][j-1]) % MOD;
      }
    }
  }

  cin>>N;
  FOR(n,N){
    int t;cin>>t;
    A.pb(t);
  }

  LL ans = f(0, N) % MOD;
  cout << ans << endl;
}