#143 X marks the Spot
Now that poor Spot has gone to that great kennel in the sky, I have decided to bury him under a new square patio, using square tiles that are all the same size. The tiles along the two diagonals are to be black to form an X that marks his final resting place, and the rest of the tiles will be white.
I went to the builders’ merchant to buy the tiles, but when I arrived I had forgotten how many white tiles I needed. Was it 691? Or 916? Or something else? All I knew for sure was that the…
