ZXASCII
AUTO -1
PROG demos:fractals/sierpinski carpet
CHANGED FALSE
10 REM Sierpinski Carpet
20 FOR x=-34 TO scrw-34:
    FOR y=124 TO scrh+124:
       x1=x,y1=y,c=2
30       IF abs x1 MOD 3<>1 or y1 MOD 3<>1 THEN
          x1=x1 DIV 3:
          y1=y1 DIV 3:
          c+=1:
       Else
          go to 40:
       end if:
       if x1>0 or y1>0 then
          plot ink c;x+34,y-124:
          go to 30
       else
          PLOT x+34,y-124
40    NEXT y:
 NEXT x