#define _GLIBCXX_DEBUG
#include <bits/stdc++.h>
using namespace std;
#define pb push_back
#define mp make_pair
#define fst first
#define snd second
#define forn(i, n) for (int i = 0; i < int(n); ++i)
typedef long long ll;
typedef vector<int> vi;
typedef vector<vi> vvi;
typedef vector<ll> vll;
typedef pair<int, int> pii;
typedef vector<pii> vii;
#define sz(c) (int)(c).size()
#define all(c) (c).begin(), (c).end()

const int mod = (int)1e9 + 7;
void add (int &a, int b)
{
    a += b;
    if (a >= mod)
        a -= mod;
}
void sub (int &a, int b)
{
    a -= b;
    if (a < 0)
        a += mod;
}
int mult (int a, int b)
{
    return (ll)a * b % mod;
}

void solve (int n)
{
    vi m(n);
    forn (i, n) cin >> m[i];

    vi inv(n + 1, 1), fact(n + 1, 1), ifact(n + 1, 1);
    for (int i = 2; i <= n; i++)
    {
        inv[i] = mod - mult(mod / i, inv[mod % i]);
        assert(mult(i, inv[i]) == 1);
        fact[i] = mult(fact[i - 1], i);
        ifact[i] = mult(ifact[i - 1], inv[i]);
    }

    vector<vector<char>> srt(n + 1, vector<char>(n + 1));
    //char srt[n + 1][n + 1];
    //memset(srt, 0, sizeof srt);
    forn (i, n + 1) srt[i][i] = 1;

    forn (j, n + 1) for (int i = j - 1; i >= 0; i--)
        srt[i][j] = (srt[i + 1][j] && (i + 1 == j || m[i] <= m[i + 1]));

    vvi dp(n + 1, vi(n + 1));
    //int dp[n + 1][n + 1];
    //memset(dp, 0, sizeof dp);
    forn (i, n + 1) if (srt[0][i] && i > 0)
        dp[i][i] = 1;

    forn (i, n + 1) forn (j, n + 1) if (dp[i][j])
    {
        assert(j > 0);
        int cur = dp[i][j];
        forn (nj, j + 1) if (nj != 0)
        {
            if (i + nj > n || !srt[i][i + nj])
                break;
            int mlt = mult(fact[j], ifact[j - nj]);
            add(dp[i + nj][nj], mult(cur, mlt));
        }
    }

    int ans = 0;
    forn (i, n + 1) add(ans, dp[n][i]);
    cout << ans << endl;
}

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

    int n;
    while (cin >> n)
        solve(n);
}