/*
          ______      
||  //   | _____|   ||  //
|| //    ||         || //
||//     ||_____    ||//
||\\     | _____|   ||\\
|| \\    ||         || \\   
||  \\   ||_____    ||  \\  
||   \\  |______|   ||   \\ 
                     
*/
#include <iostream>
#include <cstdio>
#include <set>
#include <map>
#include <stack>
#include <queue>
#include <vector>
#include <cstring>
#include <iomanip>
#include <cmath>
#include <algorithm>

using namespace std;
const int N6 = 1e6 + 6, N3 = 2e3 + 6, oo = 1e9 + 9, base = 1e9 + 7;
const long long ool = 1e18 + 9;

typedef unsigned long long ull;
typedef long long ll;
typedef double ld;
typedef pair <int, int> PII;
typedef pair <ll, ll> PLL;

#define F first
#define S second
#define pb push_back
#define eb emplace_back
#define right(x) x << 1 | 1
#define left(x) x << 1  
#define forn(x, a, b) for (int x = a; x <= b; ++x)
#define for1(x, a, b) for (int x = a; x >= b; --x)
#define mkp make_pair
#define sz(a) (int)a.size()
#define all(a) a.begin(), a.end()
#define y1 kekekek

int n, pos[N3];
ll fact[N3], a[N3], cnk[N3][N3], d[N3][N3];

ll mult(ll a, ll b) {
	return (a * b) % base;
}

int main() {
	ios_base :: sync_with_stdio(0);
	cin.tie(0);

	cin >> n;
	fact[0] = 1ll;
	forn(i, 1, n) {
		cin >> a[i];
		if (i == 1 || a[i] < a[i - 1]) pos[i] = i;
		else pos[i] = pos[i - 1];
		fact[i] = mult(fact[i - 1], i);
	}

	cnk[0][0] = 1ll;
	forn(i, 1, n) {
		cnk[i][0] = 1ll;
		forn(j, 1, i) {
			cnk[i][j] = (cnk[i - 1][j] + cnk[i - 1][j - 1]) % base;
		}
	}

	forn(i, 1, n) {
		if (pos[i] == 1) d[i][i] = 1;
	}
	forn(i, 1, n) {
		for1(j, i - pos[i] + (pos[i] != 1), 1) {
			forn(k, j, i - j) {
				d[i][j] = (d[i][j] + mult(d[i - j][k], mult(cnk[k][j], fact[j]))) % base;
			}
		}
	}

	ll ans = 0;
	forn(i, 1, n)
		ans = (ans + d[n][i]) % base;
	
	cout << ans << "\n";

	return 0;
}