Question 20
A $2\times3$ rectangle is divided into six unit squares $A,B,C,D,E,F$. Each square is to be coloured using one of six colours so that no two adjacent squares have the same colour. How many distinct colourings are possible?
Adjacent means sharing a side. Colours may be reused, and it is not necessary to use all six colours. The six labelled positions remain fixed.
Adjacent means sharing a side. Colours may be reused, and it is not necessary to use all six colours. The six labelled positions remain fixed.