#include<iostream>
#define maxn 2000
#define mod 1000000007
using namespace std;

int arr[maxn];
unsigned long long stor[maxn],istor[maxn];
unsigned long long dp[maxn][maxn];

unsigned long long power(int n,unsigned long long k ,int m=1000000007)  //return n^k % m
{

 if(k==0) return 1;
 if(k==1) return n;
 unsigned long long f=power(n,k/2,m);
 unsigned long long p=(f*f)%m;
  if(k%2!=0)
  p=(p*n)%m;
  return p;
}



int main()
{
    stor[0]=1;
    istor[0]=power(stor[0],mod-2,mod);

    for(int i=1;i<maxn;i++)
    {
        stor[i]=stor[i-1]*i;
        stor[i]%=mod;
        istor[i]=power(stor[i],mod-2,mod);
    }
    //cout<<stor[5]<<" "<<stor[2];
    int t;
    t=1;

    while(t--)
    {
        int n;
        cin>>n;

        for(int i=1;i<=n;i++)
            cin>>arr[i];
        dp[n+1][0]=1;
        for(int i=n;i>0;i--)
        {
            dp[i][0]=0;
            for(int l=1;l<=n-i+1;l++)
            {
                dp[i][l]=0;
                int flag=0;
                for(int j=0;j<l-1;j++)
                {
                    if(arr[i+j]>arr[i+j+1])
                    {
                        flag=1;
                        break;
                    }
                }

                if(flag)
                    continue;
                for(int j=0;j<=l;j++)
                {
                    dp[i][l]+=(((dp[i+l][j]*stor[l])%mod)*istor[l-j])%mod;
                    dp[i][l]%=mod;
                }
            }
            for(int l=n-i+2;l<=n;l++)
                dp[i][l]=0;
        }

        unsigned long long ans=0;
        for(int i=1;i<=n;i++)
        {
            ans+=dp[1][i];
            ans%=mod;
        }
        cout<<ans<<"\n";
    }

    return 0;
}