Friday, March 20, 2009
12 pentominos walk into a bar
And 90 minutes later walk out with a completed crossword!
I've not had much of a run of luck with Oyler's numerical puzzles, being unable to finish the last two. But I liked the look of this one, it fit my interest in symmetry and topology, so I printed it off and headed to the bar with a good feeling.
Now before I left I did a little cheating and worked out the prime factors for each of the rows and columns which were not zero.
I started with the left side, switched to the right, and worked back to the middle. It was pretty generous, looking for primes first, the 11s had to be a U-shaped bit across columns 1-3. I could place the 2s and 7s from where the 11s were. Then switching to the other side, where row 12 had to be 10, 10, 10, 6, 6 and backwards from there.
I had the pentominos placed in less than an hour, and the shading figured out in another 20 minutes or so. Done!
The coloring was done starting with the 7s - choosing one color for them, meant that the 2s and 0s had to be other colors - using the 7 color for the 9s, I could use the 0 color for the 11s and back to the 2s color for the 5s. Making sure the colors alternate around the 1s gave me the rest of the shading.
This was a lot of fun, and I'd write a lot more but I'm pressed for time, so I'll put my solving notes underneath. Put your nose close to the screen and you can probably smell Asheville Brewing Company's Old School Pale Ale. The last two numerical crosswords have fallen squarely into my comfort zone, so the next one will probably trip me up altogether!
Victory to George! 2009 tally: George 8, Listener 1. Current streak: George 2.
See you next week for further adventures in symmetry!