#include<bits/stdc++.h>
using namespace std;
#define all(v) (v).begin(),(v).end()
#define pb(x) push_back(x)

#define sqr(x) ((x)*(x))
#define mp(x,y) make_pair((x),(y))
#define fast_io() ios_base::sync_with_stdio(0);cin.tie(0);
#define fi first
#define se second
#define sz(v) ((int)v.size())
typedef pair<int,int> pii;
typedef vector<int> vi;
typedef long long ll;
typedef unsigned long long ull;
typedef long double ld;
const ll MOD=(1e9 + 7);

vector<ll> sub;
ll memo[1500][1500];
ll n;
ll fact[1500];
ll com[1500][1500];
ll pot(ll x,ll y){
	if(y==0) return 1;
	if(y==1) return x;
	ll ans=1;
	if(y%2==1) ans=x;
	ll val=pot(x,y/2);
	val%=MOD;
	ans*=val;
	ans%=MOD;
	ans*=val;
	ans%=MOD;
	return ans;
	
}

ll inv(ll x){
	x%=MOD;
	x+=MOD;
	x%=MOD;
	ll ans = pot(x,MOD-2);
	ans%=MOD;
	return ans;
}

ll C(ll x,ll y){
	if(com[x][y]!=-1) return com[x][y];
	ll ans=fact[x];
	ans%=MOD;
	ans*=inv(fact[x-y]);
	ans%=MOD;
	com[x][y]=ans;
	return ans;
}

ll dp(int pos,int x){
	int max=upper_bound(sub.begin(),sub.end(),pos)-sub.begin();
	if(pos+x>sub[max]) return 0;
	if(pos+x==n) return 1;
	if(pos+x>n) return 0;
	if(memo[pos][x]!=-1) return memo[pos][x];
	ll &ans=memo[pos][x]=0;
	for(int i=1;i<=x;i++){
		ll valor=dp(pos+x,i);
		valor%=MOD;
		valor*=C(x,i);
		valor%=MOD;
		ans+=valor;
		ans%=MOD;
	}
	ans%=MOD;
	return ans;
}


int main(){
	fast_io();
	memset(memo,-1,sizeof(memo));
	memset(com,-1,sizeof(com));
	fact[0]=1;
	for(ll i=1;i<=1400;i++){
		fact[i]=i*fact[i-1];
		fact[i]%=MOD;
	}
	cin>>n;
	int val=0;
	vector<int> v(n);
	for(int i=0;i<n;i++){
		cin>>v[i];
		if(v[i]<val){
			sub.pb(i);
		}
		val=v[i];
	}
	sub.pb(n);
	//for(int i=0;i<sz(sub);i++) cout<<sub[i]<<endl;
	ll ans=0;
	for(int i=1;i<=sub[0];i++){
		ans+=dp(0,i);
		ans%=MOD;
	}
	ans%=MOD;
	cout<<ans<<endl;

	return 0;
}