Question 6
Three numbered tiles are arranged in a tray as shown:
| 1 | 2 |
|---|---|
| 3 | |
Show that we cannot interchange the $1$ and the $3$ by a sequence of moves where we slide a tile to the adjacent vacant space.
| 1 | 2 |
|---|---|
| 3 | |
Show that we cannot interchange the $1$ and the $3$ by a sequence of moves where we slide a tile to the adjacent vacant space.