#include <cinttypes>
#include <cstdint>
#include <cstdio>
#include <cstring>
using namespace std;
#define sol 1200
#define MOD 1000000007
int a[sol];
int64_t rep[sol+1][sol+1];
int64_t f[sol+1][sol+1];
int64_t temp[sol+1];
void answer(){
	int64_t p = 1LL;
	temp[0] = 1;
	for (int v = 1 ; v <= sol ; ++v){ 
	temp[v] = p = (p*v) % MOD; 
	}
}
int64_t result(int a1 , int b1){
	if (rep[a1][b1] >= 0){ 
	return rep[a1][b1]; 
	}
	if (a1 < b1){ 
	return 0; 
	}
	if (b1 == 0){
		rep[a1][b1] = 1LL;
	} else{
		rep[a1][b1] = (result(a1-1 , b1) + result(a1-1 , b1-1)) % MOD;
	}
	return rep[a1][b1];
}

int main() {
	int a1; 
	scanf("%d",&a1);
	for (int v = 0 ; v < a1 ; ++v){ 
	scanf("%d",&a[v]); 
	}
	memset(f , 0 , sizeof(f));
	memset(rep , -1 , sizeof(rep));
	answer();
	f[a1][0] = 1;
	for (int v = a1-1 ; v >= 0; --v){
		int x = 0,k = -1;
		for (int u = v ; u < a1 ; ++u){
			if (a[u] <= k){ 
			break; 
			}
			k = a[u];
			++x;
		}
		for (int u = 1 ; u <= x ; ++u){
			for (int b = 0 ; b <= u ; ++b){
				int64_t y = result(u , b);
				int64_t z = (((temp[b]*y) % MOD)*f[v+u][b]) % MOD;
				f[v][u] = (f[v][u]+z) % MOD;
			}}}
	int64_t t = 0LL;
	for (int v = 1 ; v <= a1 ; ++v){ 
	t = (t+f[0][v])%MOD; 
	}
	printf("%" PRId64 "\n", t);
	return 0;
}