#include <math.h>
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <assert.h>
#include <limits.h>
#include <stdbool.h>
 
#define MAXN 1200
#define MOD 1000000007
 
int M[MAXN];
long dp[MAXN+1][MAXN+1];
long fact[MAXN+1];
long combination[MAXN+1][MAXN+1];
 
void cal_factor() {
    long v = 1;
    fact[0] = 1;
    for (int i=1; i<=MAXN; ++i)
    {
        fact[i] = v = (v * i) % MOD;
    }
}
 
long cal_combi(int n, int m) {
    if (combination[n][m] >= 0) { return combination[n][m]; }
    if (n < m) { return 0; }
    if (m == 0)
    {
        combination[n][m] = 1;
    }
    else
    {
        combination[n][m] =
            (cal_combi(n-1, m-1) + cal_combi(n-1, m)) % MOD;
    }
 
    return combination[n][m];
}
 
int main()
{
    int n; scanf("%d", &n);
    for (int i=0; i<n; ++i)
    {
        scanf("%d", &M[i]);
    }
    memset(dp, 0, sizeof(dp));
    memset(combination, -1, sizeof(combination));
    cal_factor();
    dp[n][0] = 1;
 
    for (int i=n-1; i>=0; --i)
    {
        int mx = 0, last = -1;
        for (int j=i; j<n; ++j)
        {
            if (M[j] <= last)
            {
                break;
            }
            last = M[j];
            ++mx;
        }
 
        for (int j=1; j<=mx; ++j)
        {
            for (int k=0; k<=j; ++k)
            {
                long c = cal_combi(j, k);
                long tmp = (((fact[k]*c) % MOD)*dp[i+j][k]) % MOD;
                dp[i][j] = (dp[i][j] + tmp) % MOD;
            }
        }
    }
 
    long ans = 0;
    for (int i=1; i<=n; ++i)
    {
        ans = (ans + dp[0][i]) % MOD;
    }
    printf("%ld\n", ans);
    return 0;
}