Regruntled.com

From my AARP newsletter, right after I complain about the Xmas Quadoku requiring too much hand-eye coordination:

8. Leave your comfort zone. Getting good at sudoku? Time to move on. Brain teasers don’t form new neural connections once you’ve mastered them. So try something that’s opposite your natural skills: If you like numbers, learn to draw. If you love language, try logic puzzles.

AARP has a point.  If I can solve the sudokus in the newspaper too easily, I’m not not getting as much benefit from them.  However, forming neural connections takes a lot of repetition, and repetition takes motivation.  If the activity isn’t intrinsically motivating, and the sudokuholics out there know exactly what I mean, “leave your comfort zone” becomes “force yourself to do something you don’t enjoy”, and who wants to live like that?  I wouldn’t recommend sudokus to someone who doesn’t like logic puzzles.  Give it a try, sure, why not?  But if it doesn’t grab you, try something else.

Move your mouse over the image!  This is one of those silly JavaScript things that I saw on the net, so I adapted it to a color sudoku. 

A new puzzle from the makers of Sudoku Ball.  There are 16 symbols, and 6 4-by-4 blocks arranged on a sphere, although it might as well be a cube.  The sudoku rules apply: symbols are used once and once in each block, row or column.  The catch here is that the rows and columns extend around the sphere.

In a 16-by-16 sudoku, there are 16 4-by-4 blocks.  Each block interacts with the other 3 blocks horizontally, and the other three blocks vertically, for a total of 6 blocks.  In the Quadoku, each block interacts with all 5 other blocks, but it interacts with the block on the other side of the sphere twice, once with the rows and once with the columns.  So, in a way, each block is involved in 6 block-to-block interactions, just as in the 16-by-16 sudoku.  The difference is that every block interacts with every other block, while in a 16-by-16 sudoku, each block has 9 other blocks that it doesn’t interact with at all. 

6 blocks times 16 cells is 96 cells, compared to 81 cells in a 9-by-9 sudoku and 256 cells in a 16-by-16 sudoku.  With fewer cells and more interconnections, I’d expect it to be a more interesting puzzle than a 16-by-16 sudoku.

In a flat sudoku, I can see everything at once.  I can follow rows and columns with my eyes.  With the Quadoku, I can only see one block at a time and have to manipulate the controls to see the others.  The opposite block is always either flipped vertically (top and bottom) or flipped horizontally (left and right) from the way I last saw it, depending on whether I’m navigating North and South, or navigating East and West.  This is a problem, because I have only so many brain cells left, and I want to use them solving the logic problem.  I don’t want to waste them on hand-eye coordination to manipulate the controls.

I suppose it gets easier with practice.  The more I remember about the contents of the unseen blocks, the less I have to turn the sphere around.  Two-dimensional representations of three-dimensional puzzles are awkward.  What I’d really like to see is an actual object that I can hold in my hands while I solve the puzzle.

Conceptis is launching a new puzzle.  A sample puzzle is on the left, the solution on the right.  The numbers obey the same row and column restrictions as sudoku.  The blocks have to satisfy the math clues in the upper left.  For example, 20X means that the three numbers have to satisfy A * B * C = 20.  Might be 1, 4 and 5 or 2, 2 and 5.  The interesting thing about these puzzles is that they start out with no digits filled in.

I’ve been solving Conceptis sudokus in the newspaper for some time now.  My only complaint is that they’re too easy.  The KenDokus look pretty easy too.  The 3X block has to be 1, 1 and 3 with the 3 in the corner to prevent the 1s from being in the same row or column.  The same is true of the 5X block since 5 is also prime.  So we already have four of the 1s filled in, and the row and column constraints leave only one spot for the fifth 1.  And so forth.  Too easy.  Maybe a 9-by-9 KenDoku would be more challenging.

I’m usually skeptical of attempts to market variations of a classic puzzle.  These things seem like solutions in search of a problem, or products in search of a market.  I don’t want something similar to a sudoku, but different.  I don’t want:

New!  Improved!  Now with baking soda!

I want something exactly like a sudoku, but harder.

Somehow I had “sudoku” and “poetry” in my brain at the same time.  I was going to take nine words and rearrange them into a nine-line poem according to a sudoku.  But which nine words?  When the going gets tough, the tough start googling.  You just never know what you’ll find.

KoolAid Report has a haiku:

Cursed sudoku!
Vile number matrix from hell!
Addict me no more!

Julian from Sydney tells a great story about delivering this poem at an open-mike night:

“Sometimes it feels like you are trapped in a cell, bound by constraints…
surrounded by squares.

You can almost feel the eyes watching you, scrutinising you with care…
working out your position…
your value…

It may help you to know that there are others out there like you -
equal to you.
Oh, sure, they are kept away from your vicinity,
away from your line of sight…
but they are there, and they indirectly influence you,
just as you… indirectly influence them.

Every day there is a new problem!
Every day… a new solution to be found.”

Rob Mackenzie from Edinburgh published this one:

Girl Playing Sudoku on the Seven-Fifteen

I sit down opposite. She doesn’t blink

or cough, her pencil-scratch the only noise

beyond the train’s dull chit-chat. Teenage boys

slouch up the centre-aisle, unleash the stink

of Lynx. She keeps on scrawling to the brink

of suffocation. I admire her poise,

open windows, plumb my brain for ploys

to start a conversation. I can’t think.

Our eyes squint out of sync. Although I stare,

I don’t dare interrupt her concentration

and when she finally completes the square

I focus on the floor. One hesitation

begins a chain. I set up solitaire.

The train heaves on, already past my station.

FM Vorassi at Deviant Art took a sudoku and replaced the ones with one-letter words, the twos with two-letter words and so on.

Butcher’s bloody cleaver hangs high on a varnished peg;
Here am I: primitive; pierce and sever, decimate, debauch
Carve and subjugate, leaving a bloodied bovine or lamb.
Yet I rekindle broken lives; resurrect mangled dead, or
Recompose, mincing.  Do they see, I cleverly create steak,
Shanks, chops – meat! - an abattoir maestro and I transcend
‘Artisan’.  Thickhead cattle I up – prime beef now triumphs -
A conquest!  Ruler and unequaled King of farmer’s market;
To them, who provides quality, brings exquisite taste?  I.

Oulipien Dax Bayard-Murray uses sudoku as an aid to generating poetry.

Colored Heart from Quezon City has a poem  about Sudoku Fever.

Eduard Söllner has some sudoku-inspired art.

Here the cells are a little bit rounder, offset slightly, and overlapped a bit. 

This is something like my Frosted sudoku, but instead of adding white pixels at random, I interpolated the colors.  In other words, if my randomizing function said that a certain pixel had a 50% chance of being blue, and a 50% chance of being white, instead of flipping a coin to make it one or the other, I just mixed the paint and made the pixel halfway between blue and white.

Here is yet another experiment in sudoku graphics.  I took out the grid lines and added white pixels somewhat randomly, but more likely near the edges than the centers of the cells.