6. For a polygon, define a "growth" operation: as shown in Figure 1, change one of its sides $\mathrm{AB}$ into an outward convex polyline $\mathrm{ACDEB}$, where $\mathrm{C}$ and $\mathrm{E}$ are the trisection points of $\mathrm{AB}$, and points $\mathrm{C}, \mathrm{D}, \mathrm{E}$ can form an equilateral triangle. Therefore, for an equilateral triangle with a side length of 9, after two "growth" operations (as shown in Figure 2), the perimeter of the resulting shape is $\qquad$; after four "growth" operations, the perimeter of the resulting shape is $\qquad$
$48 ; 256 / 3$