#include <bits/stdc++.h>
using namespace std;
const long long MAXN = 1205; 
long long n; 
long long arr [MAXN]; 
long long farthest [MAXN]; 
long long dp [MAXN][MAXN];
long long fact [MAXN]; 
long long inv_fact [MAXN]; 
long long choose [MAXN][MAXN]; 
const long long MOD = 1e9 + 7; 
long long powm (long long a, long long b){
    if(b==0)return 1; 
    long long ke = powm(a,b/2); 
    ke=(ke*ke)%MOD; 
    if (b&1)ke=(ke*a)%MOD; 
    return ke; 
}
int main(){
    fact[0]=1;
    for (long long i=1;i<MAXN;i++)fact[i]=(1LL*i*fact[i-1])%MOD; 
    for (long long i=1; i<MAXN; i++)inv_fact[i]=powm(fact[i],MOD-2); 
    ios_base::sync_with_stdio(0); 
    cin >> n; 
    for (long long i=0; i<MAXN; i++) choose[i][0]=1; 
    for (long long i=1; i<MAXN; i++){
        for (long long j=1; j<MAXN; j++){
            choose[i][j]=(choose[i-1][j]+choose[i-1][j-1])%MOD; 
        }
    }
    farthest[n] = n; 
    for (long long i=1; i<=n; i++) cin >> arr[i]; 
    for (long long i=n-1; i>=1; i--){
        farthest[i] = farthest[i+1]; 
        if (arr[i]>arr[i+1]) farthest[i]=i; 
    }
    dp[n+1][0]=1; 
    long long tot=0; 
    for (long long i=n; i>=1; i--){
        for (long long j=1; j<=n; j++){
            if (farthest[i]-i+1<j) continue; 
            dp[i][j]=fact[j];
            long long tot=0;
            for (long long k=0; k<=j; k++){
                // i+j
                tot=(tot+choose[j][j-k]*dp[i+j][k])%MOD;
            }
            dp[i][j]*=tot;
            dp[i][j]%=MOD; 
        }
    }
    for (long long j=1; j<=n; j++){
        tot+=dp[1][j]*inv_fact[j]; 
        tot%=MOD; 
    }
    cout << tot << '\n'; 
    return 0; 
}