// author: gary
#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef pair<int, int> pii;

#define ALL(x) (x).begin(), x.end()

const int inf = 1e9;
const int maxn = 1500;
const int mod = 1e9 + 7;

void madd(int& a, int b) {
  a += b;
  if(a >= mod)
    a -= mod;
}

int mul(int a, int b) {
  return (1LL * a * b) % mod;
}

int mpow(int a, int n) {
  int r = 1;
  while(n > 0) {
    if(n & 1)
      r = mul(r, a);
    a = mul(a, a);
    n >>= 1;
  }
  return r;
}


int n;
int a[maxn];
int s[maxn];
int f[maxn], fi[maxn];
int dp[maxn][maxn];

int sorted(int i, int j) {
  return j - i == s[j-1]-s[i-1];
}

int ncr(int n, int k) {
  return mul(f[n], mul(fi[n-k],fi[k]));
}

int rec(int i, int j) {
  if(i == n + 1) return 1;
  int& ans = dp[i][j];
  if(ans != -1) return ans;
  ans = 0;
  for(int k = 0; k < j; k++) 
    if(i + j - k - 1 <= n && sorted(i, i + j - k - 1))
      madd(ans, mul(rec(i + j - k, j - k), mul(f[j], fi[k])));
  return ans;
}

int main() {
  scanf("%d", &n);
  for(int i = 1; i <= n; i++) 
    scanf("%d", a + i);
  for(int i = 1; i < n; i++) {
    s[i] = a[i] < a[i + 1];
    s[i] += s[i-1];
  }

  f[0] = fi[0] = 1;
  for(int i = 1; i < maxn; i++) {
    f[i] = mul(f[i-1], i);
    fi[i] = mul(fi[i-1], mpow(i, mod-2));
  }

  memset(dp, -1, sizeof dp);

  int res = 0;
  for(int k = 1; k <= n && sorted(1, k); k++) {
    madd(res, rec(1+k, k));
  }
  printf("%d\n", res);
  return 0;
}