#include <bits/stdc++.h>
#include <cmath>
#include <vector>
#include <set>
#include <map>
#include <stack>
#include <queue>
#include <deque>
#include <string>
#include <fstream>
#include <iostream>
#include <algorithm>
#include <iomanip>
#include <numeric>

using namespace std;

typedef vector<int> vi;
typedef pair<int, int> ii;
typedef vector<long> vl;
typedef long long ll;
typedef pair<long long, long long> llll;
typedef vector<long long> vll;
#define matrix(a) vector< vector<a> >
#define sz(a) int((a).size()) 
#define ite(v) v::iterator
#define lop(i,a,b) for (int i=a; i<=b; i++)
#define vlop(i,v) lop(i,0,sz(v)-1)
#define vlop1(i,v) lop(i,1,sz(v)-1)
#define rlop(i,a,b) for (int i=b; i>=a; i--)
#define vrlop(i,v) rlop(i,0,sz(v)-1)
#define vrlop1(i,v) rlop(i,1,sz(v)-1)
#define printv(i,v) vlop(i,v)cout<<v[i]<<" "
#define all(s) (s).begin(),(s).end()
#define isthere(c,x) ((c).find(x) != (c).end()) 
#define cisthere(c,x) (find(all(c),x) != (c).end())
#define pb push_back
#define fill(s,v) memset(s,v,sizeof(s))
#define enter cout<<endl
const long long M=1000000007;
long long euclidean(long long a, long long b) {
	vector<long long> r = { a,b };
	vector<long long> s = { 1,0 };
	vector<long long> t = { 0,1 };
	int i;
	long long q;
	while (true) {
		i = r.size() - 1;
		r.pb(r[i - 1] % r[i]);
		q = r[i - 1] / r[i];
		s.pb(s[i - 1] - s[i] * q);
		if (r[i + 1] == 0)break;
	}
	if (s[i]<0)s[i] += M;
	if (s[i] >= M)s[i] -= M;
	return s[i];
}
int main(){
    int n;
    cin >> n;
    vll fact(n+1,1),invfact(n+1,1);
    vlop1(i,fact){
        fact[i]=fact[i-1]*i%M;
        invfact[i]=euclidean(fact[i],M);
    }
    vector<int> m(n);
    for(int m_i = 0; m_i < n; m_i++){
       cin >> m[m_i];
    }
    vi sec;
    int head=0;
    vlop1(i,m){
        if(m[i]<m[i-1]){
            sec.pb(head);
            head=i;
        }
    }
    sec.pb(head);
    matrix(ll) p(n+1,vll(n+1,0));
    lop(i,0,sz(sec)-1){
        int sectstart=sec[i];
        int sectend;
        if(i==sz(sec)-1)sectend=n-1;
        else sectend=sec[i+1]-1;
        if(!i){
            lop(j,sectstart+1,sectend+1){
                lop(k,1,j/2){
                    lop(l,k,j-k){
                        p[j][k]+=(p[j-k][l]*fact[l]%M*invfact[l-k]%M);
                        p[j][k]%=M;
                    }
                }
                    p[j][j]=1;
                /*printv(k,p[j]);
                enter;*/
            }
    }
    else{
        lop(j,sectstart+1,sectend+1){
                lop(k,1,j/2){
                    if(j-k>=sec[i]){
                    lop(l,k,j-k){
                        p[j][k]+=(p[j-k][l]*fact[l]%M*invfact[l-k]%M);
                        p[j][k]%=M;
                    }
                    }
                }     
            /*printv(k,p[j]);
                enter;*/
            }

    }
    }
    ll result=0;
    vlop1(i,p[n]){
        result+=p[n][i];
        result%=M;
    }
    cout<<result;
    return 0;
}