#include <iostream>
#include <cstdio>
#include <vector>
#include <set>
#include <deque>
#include <algorithm>
#include <queue>
#include <cmath>
#include <map>
#include <complex>
#include <cstring>
#include <cassert>
#include <bitset>

using namespace std;
#define rep(i, a, b) for(int i = (a); i < (b); i++)
#define repd(i, a, b) for(int i = (a); i > (b); i--)
#define forIt(it, a) for(__typeof((a).begin()) it = (a).begin(); it != (a).end(); it++)
#define forRev(it, a) for(__typeof((a).rbegin()) it = (a).rbegin(); it != (a).rend(); it++)
#define ft(a) __typeof((a).begin())
#define ll long long
#define ld long double
#define fi first
#define se second
#define mk make_pair
#define pb push_back
#define sz(a) (int)(a).size()
#define all(a) (a).begin(), (a).end()
#define Rep(i,n) for(int i = 0; i < (n); ++i)
#define bitcount(n) __builtin_popcountll(n)
#define randchar() ((rand() % 26) + 'a')


typedef complex<ld> cplex;
typedef vector<int> vi;
typedef pair<int, int> ii;
typedef pair<ii, int> iii;
typedef vector<ii> vii;
typedef vector<iii> viii;

const int N = 1200 + 7;
const int M = N;
const int inf = 1e9 + 7;
const long long linf = 1ll * inf * (inf - 1);
const double pi = acos(-1);
const double eps = 1e-7;
const bool multipleTest = 0;

int lt[N], invlt[N];

int inverse(int x, int n){
    int r = n, newr = x;
    int t = 0, newt = 1;
    while (newr > 0){
        int q = r / newr;
        
        int tmp = newr;
        newr = r % newr;
        r = tmp;
        
        tmp = newt;
        newt = t - q * newt;
        t = tmp;
    }
    if (t < 0) t += n;
    return t;
}

void init() {
    lt[0] = invlt[0] = 1;
    rep(i, 1, N) {
        lt[i] = (ll) lt[i - 1] * i % inf;
        invlt[i] = inverse(lt[i], inf);
    }
}

ll DP[N][M];
int n;
int a[N];

void solve() {
    cin >> n;
    for(int i = 1; i <= n; ++i ) {
        cin >> a[i];
    }
    
    init();
    
    for(int i = n; i > 0; --i) {
        bool ok = true;
        for(int j = i; j <= n && j - i + 1 < M; ++j) {
            if (j > i && a[j] < a[j - 1]) ok = false;
            if (!ok) break;
            int k = j - i + 1;
            
            if (j == n) DP[i][k] = 1;
            else {
                
                for(int t = 1; t <= k; ++t) {
                    DP[i][k] += DP[j + 1][t] * lt[k] % inf * invlt[k - t];
                    if (DP[i][k] >= linf) DP[i][k] -= linf;
                }
            }
            
            DP[i][k] %= inf;
        }
    }
    
    ll ans = 0;
    for(int i = 1; i < M; ++i) ans = (ans + DP[1][i]) % inf;
    cout << ans << '\n';
    
}


void test() {
    freopen("in.txt", "w", stdout);
    for(int i = 0; i < 50000; ++i) {
        printf("%c", randchar());
    }
    
    cout << '\n' << 100000 << '\n';
    
    rep(i, 0, 100000) {
        rep(t, 0, (rand() % 4) + 1) printf("%c", randchar());
        printf(" ");
        rep(t, 0, (rand() % 4) + 1) printf("%c", randchar());
        printf("\n");
    }
    
}


int main() {
#ifdef _LOCAL_
    freopen("in.txt", "r", stdin);
#endif
    //    freopen("out.txt", "w", stdout);
    
    
    
    int Test = 1;
    if (multipleTest) {
        cin >> Test;
    }
    for(int i = 0; i < Test; ++i) {
        //        printf("Case #%d: ", i + 1);
        
        solve();
    }
    
#ifdef _LOCAL_
    cout<<"\n" << 1.0 * clock() / CLOCKS_PER_SEC<<endl;
#endif
}