#include<bits/stdc++.h>
#define ll long long
#define MOD 1000000007
using namespace std;

ll dp[2010][2010];
ll a[2010];
ll n;
ll fact[2010], inv[2010];
ll power(ll a, ll b, ll mod){
	ll ret = 1;
	while(b){
		if(b&1)ret = ret*a % mod;
		a = a*a % mod;
		b >>= 1;
	}
	return ret;
}

ll solve(ll idx, ll k){
//	cout<<idx<<" "<<k<<endl;
	if(idx == n+1)return 1;
	if(dp[idx][k] != -1)return dp[idx][k];
	int flag=1;
	ll ret=0;
	for(int i=1; i<k; i++)
		if(a[i+idx] < a[i-1+idx]){flag=0;break;}
	if(!flag)ret = 0;
	else{
		int temp = min(idx+k, n+1);
		int diff = min(k, n-temp+1);
		if(temp == n+1)ret = solve(temp, diff);
		for(int i=1; i<=diff; i++){
			ll kci = (fact[k])%MOD;
//			cout<<kci<<endl;
			kci = (kci*inv[k-i])%MOD;
			ret = (ret + (kci*solve(temp, i))%MOD)%MOD;
		}
	}
	return dp[idx][k] = ret;
}

int main(){
	memset(dp, -1, sizeof(dp));
	cin>>n;
	fact[0] = 1;
	inv[0] = 1;
	for(int i=1; i<=n; i++){
		fact[i] = (fact[i-1]*i)%MOD;
		inv[i] = power(fact[i], MOD-2, MOD);
	}
	for(int i=1; i<=n; i++)cin>>a[i];
	ll ans = 0;
	for(int i=1; i<=n; i++){
//		cout<<i<<":"<<endl;
		ll x= solve(1, i);
	//	cout<<"h "<<x<<endl;
		ans = (ans+x)%MOD;
	}
	cout<<ans<<endl;
	return 0;
}