#include "bits/stdc++.h"

using namespace std;

typedef long long ll;
typedef pair < int, int > ii;

const int N = 1200 + 5;
const int mod = 1e9 + 7;

inline int add(int x, int y) {
    return x + y >= mod ? x + y - mod : x + y;
}

inline int mul(int x, int y) {
    return (ll) x * y % mod;
}

int fe(int x, int k) {
    int res = 1;
    while(k) {
        if(k & 1)
            res = mul(res, x);
        x = mul(x, x);
        k >>= 1;
    }
    return res;
}

int n;
int a[N], fact[N], inv[N], dp[N][N];
bool sorted[N][N];

int c(int n, int r) {
    return mul(fact[n], mul(inv[r], inv[n - r]));
}

int f(int sum, int last) {
    if(sum == n)
        return 1;
    int &r = dp[sum][last];
    if(r != -1)
        return r;
    r = 0;
    for(int i = 1; i <= last and sum + i <= n; i++) {
        if(sorted[sum + 1][sum + i])
            r = add(r, mul(mul(f(sum + i, i), c(last, i)), fact[i]));
    }
    return r;
}

int main() {
    
    fact[0] = inv[0] = 1;
    
    for(int i = 1; i < N; i++) {
        fact[i] = mul(fact[i - 1], i);
        inv[i] = mul(inv[i - 1], fe(i, mod - 2));
    }
    
    scanf("%d", &n);
    
    for(int i = 1; i <= n; i++) {
        scanf("%d", a + i);
    }
    
    for(int i = 1; i <= n; i++) {
        sorted[i][i] = 1;
        for(int j = i + 1; j <= n; j++) {
            if(a[j] < a[j - 1])
                break;
            sorted[i][j] = 1;
        }
    }
    
    memset(dp, -1, sizeof(dp));
    
    int ans = 0;
    
    for(int i = 1; i <= n; i++)
        ans = add(ans, f(i, i) * sorted[1][i]);
    
    printf("%d\n", ans);
    
    return 0;
    
}