Question

A cell is good if the board without this cell can be tiled by domino 1\times 21×2 tiles. What is the number of good cells? (Just write a number in the answer field)
(In other words, you want to delete one cell in such a way that the rest can be tiled. How many options do you have? For example, if you delete the left upper corner, you can tile the rest using vertical tiles in the first column and horizontal tiles elsewhere. So the left upper corner is good. Some other cells (e.g., the other corners) are good, but not all. You need to count the good cells.)

Answer 1

Answer:

I don't know the answer because It is a very big paragraph

Answer 2

Answer:

13

Step-by-step explanation:

5x5 square :

   * We need to place 1x2 tiles over remaining cells without current cell to find it good or bad.

   * So, for first cell, it is good. We can place tiles over remaining cells.

   * But when we neglect 1x2 cell we can't place. vice versa....

(1x1 cell is good)   (1x2 is bad)      (1x3 good)       (1x4 bad)           (1x5 is good)

(2x1 is bad)           (2x2 is good)   (2x3 is bad)     (2x4 is good)    (2x5 is bad)

So this shows there is logic to place tiles over cells. This wil repeated for every iterations( therefore, two rows).

row 1 :  g b g b g

row 2 : b g b g b

row 3 : g b g b g

row 4 : b g b g b

row 5 : g b g b g