import java.util.*;
import java.io.*;

public class University_Codesprint_2_E {

	static BufferedReader br;
	static PrintWriter out;
	static StringTokenizer st;

	static final int MOD = (int)(1e9 + 7);
	
	static int N;
	static int[] val, seg;
	static long[] fact;
	static long[][] dp, choose;
	
	public static void main (String[] args) throws IOException {
		br = new BufferedReader(new InputStreamReader(System.in));
		out = new PrintWriter(new OutputStreamWriter(System.out));
		//br = new BufferedReader(new FileReader("in.txt"));
		//out = new PrintWriter(new FileWriter("out.txt"));

		N = readInt();
		val = new int[N];
		seg = new int[N << 2];
		fact = new long[N + 1];
		
		fact[0] = 1;
		for (int i = 1; i <= N; i++)
			fact[i] = (fact[i - 1] * i) % MOD;
		
		for (int i = 0; i < N; i++)
			val[i] = readInt();
		
		update(1, 0, N - 1, 0, 0, 1);
		int last = 0;
		for (int i = 1; i < N; i++) {
			if (val[i] < val[i - 1])
				last = i;
			update(1, 0, N - 1, last, i, 1);
		}
		
		dp = new long[N + 1][N + 1];
		for (int i = 0; i <= N; i++)
			for (int j = 0; j <= N; j++)
				dp[i][j] = -1;

		choose = new long[N + 1][N + 1];
		for (int i = 0; i <= N; i++)
			for (int j = 0; j <= i; j++)
				choose[i][j] = (j == 0 || i <= 1) ? 1 : (choose[i - 1][j - 1] + choose[i - 1][j]) % MOD;
		
		out.println(compute(0, N));
		out.close();
	}
	
	static long compute (int n, int k) {
		if (n == N)
			return 1;
		if (dp[n][k] != -1)
			return dp[n][k];
		long ret = 0;
		int len = Math.min(k, query(1, 0, N - 1, n));
		for (int i = 1; i <= len; i++)
			ret = (ret + (n == 0 ? 1 : fact[i] * choose[k][i] % MOD) * compute(n + i, i)) % MOD;
		return dp[n][k] = ret;
	}

	static void update (int n, int l, int r, int ql, int qr, int val) {
		if (ql == l && qr == r) {
			seg[n] += val;
			return;
		}
		pushDown(n);
		int mid = (l + r) >> 1;
		if (qr <= mid)
			update(n << 1, l, mid, ql, qr, val);
		else if (ql > mid)
			update(n << 1 | 1, mid + 1, r, ql, qr, val);
		else {
			update(n << 1, l, mid, ql, mid, val);
			update(n << 1 | 1, mid + 1, r, mid + 1, qr, val);
		}
	}
	
	static int query (int n, int l, int r, int x) {
		if (l == x && x == r)
			return seg[n];
		pushDown(n);
		int mid = (l + r) >> 1;
		if (x <= mid)
			return query(n << 1, l, mid, x);
		else
			return query(n << 1 | 1, mid + 1, r, x);
	}
	
	static void pushDown (int n) {
		if (seg[n] != 0) {
			seg[n << 1] += seg[n];
			seg[n << 1 | 1] += seg[n];
			seg[n] = 0;
		}
	}
	
	static String next () throws IOException {
		while (st == null || !st.hasMoreTokens())
			st = new StringTokenizer(br.readLine().trim());
		return st.nextToken();
	}

	static long readLong () throws IOException {
		return Long.parseLong(next());
	}

	static int readInt () throws IOException {
		return Integer.parseInt(next());
	}

	static double readDouble () throws IOException {
		return Double.parseDouble(next());
	}

	static char readCharacter () throws IOException {
		return next().charAt(0);
	}

	static String readLine () throws IOException {
		return br.readLine().trim();
	}
}