Week - OCTOBER 20

Last week we learn Sierpinski triangle - an interesting triangle model!                                                  

There is an example:

(require picturing-programs)
(triangle 25 "solid" "red")

（define (stack an-image)

          (above an-image (beside an-image an-image)))

(define (Sierpinski n)

     (cond [ ( zero? n ) 🔺]

               [else (stack ( Sierpinski (- n 1)))]))

-------------------------------------------

（stack (Sierpinski (- 1 1)))

•it will appears a big triangle with four small equally triangle.

That because (Sierpinski 0) is a single triangle, (stack 0) means repeated addition other three triangles (a big triangle with four small equally triangle)