import java.math.BigInteger;
import java.util.*;

/**
 *
 * @Riya Bhardwaj
 */
public class Hack3 {
    static BigInteger sum=new BigInteger("0");static int f=0;
    static void cal(long arr[],int n)
    {
       int i;
       int n2=0;int nc=n;
      while(nc>=1){
          n2+=nc;nc-=1;}
        long[] arr2=new long[n2];
      for( i=0;i<n;i++)
      {
          arr2[i]=arr[i];
          sum=sum.add(BigInteger.valueOf(arr[i]));
      }
      long temp2=0;int i2;
      i2=i;int y=i-2;
      i=0;
      while(i2<n2)
      {
          if(arr2[i]>arr2[i+1])
              temp2=arr2[i];
          else
              temp2=arr2[i+1];
          
          sum=sum.add(BigInteger.valueOf(temp2));
          arr2[i2]=temp2;
          i2+=1;
          if(i==y)
          {
              i=i+2;y=i2-2;
          }
          else
              i+=1;
      }
      f+=1;
      if(f==1)
      {
          sum=BigInteger.ZERO;
      cal(arr2,n2);
    }
    }
    public static void main(String[]args)
    {
      Scanner sc=new Scanner(System.in);
      int n=sc.nextInt();
      long arr[]=new long[n];
      for(int i=0;i<n;i++)arr[i]=sc.nextLong();
      
      cal(arr,n);
          System.out.println(sum.mod(BigInteger.valueOf(1000000007)));
    }
}