The Sierpinski triangle of order 4 should look like this:

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

Uxntal

( uxncli sierpinski.rom )

|100 @on-reset ( -> )

	#10 STHk #01 SUB
	&ver ( -- )
		DUP
		#00 EQUk ?{
			&pad ( -- )
				#2018 DEO
				INC GTHk ?&pad
		} POP 
		#00
		&fill
			ANDk #202a ROT ?{ SWP } POP #18 DEO
			#2018 DEO
			INC ADDk STHkr LTH ?&fill
		POP2
		#0a18 DEO
		#01 SUB DUP #ff NEQ ?&ver
	POP POPr

BRK

fy

:N 16;
N [ dup                         (y) 
    [' .c] dotimes              (print padding)
    N [ dup                     (x)
        over2 drop 1-           (y' = y - 1)
        swap N !-               (x' = N - x)
        &                       (x' & y')
        \'  \'* ifte .c ' .c ]  (print * or space)
    dotimes .nl]       
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