Question 85
In a table with two rows and five columns, each of the squares is coloured black or white according to the following rules:
* Two adjacent columns may never have the same number of black squares.
* Two $2 \times 2$-squares that overlap in one column may never have the same number of black squares.
How many possible colourings of the table comply with these rules?
* Two adjacent columns may never have the same number of black squares.
* Two $2 \times 2$-squares that overlap in one column may never have the same number of black squares.
How many possible colourings of the table comply with these rules?