#define _CRT_SECURE_NO_WARNINGS
#include <iostream>
#include <algorithm>
#include <unordered_set>
#include <vector>
#include <cmath>
#include <string>
#include <set>
#include <map>
#include <cstdio>
#include <functional>
#include <random>
#include <ctime>
#include <cassert>
#include <unordered_map>
#include <omp.h>
#include <math.h>

using namespace std;

#define N 1500
#define M 1850
mt19937 gen;
#define forn(i, n) for (int i = 0; i < n; i++)
#define piii pair<int, pair<int, int>>
#define pii pair<int, int>
#define forlrv(i, l, r) for (int i = r; i >= l; i--)
#define y(p) p.second
#define mp make_pair
#define mpp(a, b, c) mp(a, mp(b, c))
typedef long long ll;
typedef unsigned long long ull;
#define forlr(i, l, r) for (int i = l; i <= r; i++)
#define p p2

int n;
int w[N];

ll d[N][N];

ll f[N], tr[N][N];

ll mod = 1000000007;

void solve()
{
	cin >> n;
	forlr(i, 1, n)
		cin >> w[i];

	forlr(i, 1, n)
	{
		if (w[i] < w[i - 1])
			break;
		d[i][i] = 1;
	}

	forlr(i, 0, n)
		tr[i][0] = 1;

	forlr(i, 1, n)
		forlr(j, 1, i)
			tr[i][j] = (tr[i - 1][j - 1] + tr[i - 1][j]) % mod;

	f[0] = 1;
	forlr(i, 1, n)
		f[i] = (f[i - 1] * i) % mod;

	forlr(i, 1, n)
		forlr(j, 1, n)
		if (d[i][j])
			for (int u = 1; u <= j && i + u <= n; u++)
			{
				if (u > 1 && w[i + u] < w[i + u - 1]) break;
				d[i + u][u] = (d[i + u][u] + (((d[i][j] * f[u]) % mod) * tr[j][u]) % mod) % mod;
			}

	ll sum = 0;
	forlr(i, 1, n)
		sum = (sum + d[n][i]) % mod;

	cout << sum << endl;
}

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