Task
Produce an ASCII representation of a Sierpinski triangle of order   N.



Example
The Sierpinski triangle of order   4   should look like this:

                       *
                      * *
                     *   *
                    * * * *
                   *       *
                  * *     * *
                 *   *   *   *
                * * * * * * * *
               *               *
              * *             * *
             *   *           *   *
            * * * *         * * * *
           *       *       *       *
          * *     * *     * *     * *
         *   *   *   *   *   *   *   *
        * * * * * * * * * * * * * * * *



Related tasks
 Sierpinski triangle/Graphical for graphics images of this pattern. 
 Sierpinski carpet


Input "Triangle order: ";n
n = 2^n
 
For y = n - 1 To 0 Step -1
 
  For i = 0 To y
    Print " ";
  Next
 
  x = 0
 
  For x = 0 Step 1 While ((x + y) < n)
     If AND (x,y) Then
        Print "  ";
     Else
        Print "* ";
     EndIf
  Next
 
  Print
Next
End