#include<bits/stdc++.h>
#define ll  long long
typedef unsigned long long int ull;
 
using namespace std;
#define mx 100005
ll ar[mx];
ll mod ,c[1205][1205],n,dp[1205][1205];
ll fac[1205];
void ncr()
{   
      int i,r;
      fac[0]  = 1;
      fac[1] = 1;
      for(i=2;i<=1203;i++)
      fac[i] = (fac[i-1]*i)%mod;
      for(i=0;i<=1203;i++)
      {
      	for(r=0;r<=1203;r++)
      	dp[i][r] = -1;
	  }
	 for(i=0;i<=1203;i++)
	 {
	 	 for(r=0;r<=1203 && r<=i;r++)
	 	 {
	 	 	 if(r==0 || r==i)
	 	 	  c[i][r] = 1;
	 	 	 else
			   {
			      c[i][r] = (c[i-1][r-1] + c[i-1][r])%mod;	 
			   } 
		 }
	 }
	   
}
ll go(int pos,int last)
{
	if(pos>n)
	{
		return 1;
	}
	if(dp[pos][last]!=-1)
	return dp[pos][last];
	
	ll r = 0,pre,tmp;
	int i;
	pre = -1;
	
	for(i=1;i<=last;i++)
	{
		if(pos==1)
		{
			if(ar[pos+i-1]<pre)
			break;
			pre = ar[pos+i-1];
			r += go(pos+i,i);
			r = r%mod;
			
		}
		else
		{ 
		       if(ar[pos+i-1]<pre)
			   break;
			   pre = ar[pos+i-1];
			   tmp = (c[last][i]*fac[i])%mod;
				r += (tmp*go(pos+i,i))%mod;
			    r = r%mod;
			    if(pos+i>n)
			    break;
		}
	}
	return dp[pos][last] = r;
}
int main()
{
     mod = 1e9+7;
     ncr();
     int i;
     scanf("%lld",&n);
	for(i=1;i<=n;i++)
	scanf("%lld",&ar[i]);
	cout<<go(1,n)<<endl;
}