#include<bits/stdc++.h>
using namespace std;

#define MYMAXI 1200
#define MOD 1000000007

int M[MYMAXI];
long long  cache[MYMAXI+1][MYMAXI+1];
long long  facty[MYMAXI+1];
long long  combination[MYMAXI+1][MYMAXI+1];

void myfactyorial() {
	long long  v = 1LL;
	facty[0] = 1;
	for (int i=1; i<=MYMAXI; ++i) { facty[i] = v = (v * i) % MOD; }
}

long long  myfunction(int n, int m) {
	if (combination[n][m] >= 0) { return combination[n][m]; }
	if (n < m) { return 0; }
	if (m == 0) {
		combination[n][m] = 1LL;
	} else {
		combination[n][m] =
			(myfunction(n-1, m-1) + myfunction(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(cache, 0, sizeof(cache));
	memset(combination, -1, sizeof(combination));
	myfactyorial();
	cache[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 long  c = myfunction(j, k);
				long long  tmp = (((facty[k]*c) % MOD)*cache[i+j][k]) % MOD;
				cache[i][j] = (cache[i][j] + tmp) % MOD;
			}
		}
	}

	long long  ans = 0LL;
	for (int i=1; i<=n; ++i) { ans = (ans + cache[0][i]) % MOD; }
	printf("%" PRId64 "\n", ans);
	return 0;
}