Erasable Games Weblog

(Sudoku in words and pictures)

Archive for September, 2007

“Undextrous” Sudoku

Sunday, September 30th, 2007

Most of us only use our least-used hand when we are kids or if we damage our favored hand. This feature of our species, called handedness is studied at a research institute called Handedness Research Institute. The intitute’s purpose is to reduce social and educational discrimination because of the existence of left-handers.

At Indiana University, the connection between Handedness and Brain Lateralization is decribed. It turns out that Language skills are in the opposite hemisphere from the dominant hand, but not always. It seems that some left-handers can and do screw it up and have language specialization on the left side also.

As a left-hander myself, I was able to overcome the design decisions, such as of: right handed chair-desks, scizzors, Guitar string order and other presumptive creations. Chair-desks not nailed in place I rotated 45 degrees; scizzors, I flipped over and Guitar strings I restrung in the opposite order.

I delighted in getting ink, pencil lead on the outside of my left hand and ignored the smudging as I traversed the lines of the page. I tried to say the most important things on the right side of the page. Basically, I ignored the difficulties. With the advent of keyboards and typing, this inequity has been significantly reduced.

It’s a handicap in solving Sudoku this way, because you are constrained to write legibly in your unpracticed hand, slowing you down and adding to the stress of solving the puzzle. Other people might, on the other hand (no pun intended), enjoy a calming effect that concentrated focus brings.

I use my ability to solve sudoku puzzles in a timely fashion as an indicator of how mentally adept and insightful I am. When I am ill, my mental acuity drops like a rock and solving a sudoku puzzle can take days. What other method can detect that you are getting better without taking your temperature?

Liquified Sudoku

Sunday, September 23rd, 2007

Liquified Sudoku

This is Part 2 of Sudoku Media testing. (See the Will it Blend? Cartoon on August 5, 2007). Perhaps because I have acquired a bad cold does this particularly appeal to me. It’s hard to maintain the clarity to do a sudoku puzzle. Frustration abounds. Ergo, the ultimate solution.

My thanks to Vlad Balan who runs, which provides daily puzzles of varying difficulty along with Sudoku related news and a community page, which shows the twisted sudoku picture encircled.

I’m going to rest my cold now and look for a better day tomorrow.

Blank Sudoku

Sunday, September 16th, 2007

Blank Sudoku

Continuing the general theme of limitation, here’s a variant that I have devised where a blank cell plays the role of a digit, to be placed so that there is exactly one blank cell in each row, column and 3×3 block. What makes the rule amusing is that you cannot distinguish blank cells that have to be filled in with 8 of the digits and the special blank cells representing the ninth digit. I’ve not seen it in any other Sudoku variant sites, so you may be seeing it here first.

It’s abtractly identical to many of the Sudoku variants where other symbols are mapped to the digits 1-9. In this case, only one digit is mapped to blank, while the rest of the digits stay as they are.

Crossword Sudoku

Sunday, September 9th, 2007

Crossword Sudoku

I wanted to do a mash-up of Crossword and Sudoku Puzzles. Here is my contribution. It takes a while to think of interesting, non-obvious clues. Alas, these clues will probably have to suffice for all future mash-ups like this. There are just not so many synonyms for the first 9 digits! I tried not to do Fill-in clues, to minimize space. This crossword can be considered a diagramless puzzle, except the starting clues, once entered, are superceded by Sudoku logic.

Sudoku In The Dark

Sunday, September 2nd, 2007

Sudoku In The Dark

It occurred to me that this theme could benefit from a change in the point of view (no pun intended) closer to that of participant. While anyone can put on a blindfold, it is similarly possible to suffer from a power failure at night, with minimal (candle, flash) light available, or to be at a campsite at night in a remote location.

In these cases, mind maps are a way to making a changing scenario, like a puzzle persist and progress to its completion. Human nature being as it is, not many practice this technique when vision and light are plentiful, unless there is no alternative. It does offer another strong challenge to try to solve puzzles (like math problems, chess games) in your head. Blindfold Chess Tournaments have become a popular chess variation. The Math Forum at Drexel University has an archive of mental math techniques that compete or beat a calculator to the answer.

What’s the benefit? You become more portable and have less need for “stuff”.

For those in the United States, enjoy your Labor Day Weekend safely.