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Signal Pennant Sudoku

Signal Pennant Sudoku

The use of flags and pennants as communications has intrigued me. According to the Sea Flags web site, Athenian (Greek) ships were first known to signal each other with brightly colored flags. Time passed and Navies of various European countries began to devise more sophisticated communication using semaphores and flaghoists after 1750.

The current situation is depicted in the International Code of Signals and in particular, pennants representing the digits one through nine are shown in the cartoon.

It’s an easy leap to create a sudoku puzzle using these pennants as stand-ins for the normal digits. You may do this puzzle calmly and in a room that has been becalmed as well.

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Time Change Sudoku

Time Change Sudoku

In most of the United States (But not Arizona nor Hawaii), Daylight Saving Time began early this morning, March 9. I find out how many clocks I’m governed by when I do this twice-yearly ritual. Occasionally, the clocks I missed last fall are telling accurate time now and they stay unperturbed.

I found an interesting Web Site called webexhibits.org describing Daylight Saving Time and which uses a kind of a mind-map (that they call clouds or nodes) to display information, in lieu of powerpoint-like slides. For this, you must let go of outlines and hierarchy.

Wikipedia has a colored map of use and abstinence of DST (or Summer Time) Worldwide.

To honor the induced chaos of time changes, I’ve created a Sudoku Puzzle which uses analog clock faces. Take your time.

Usually at this time of year, the Yearly Sudoku World Championship announces itself. Based on a cursory web search, The 2008 Sudoku World Championship will be held on April 14-17, 2008 in Goa, India on the West Coast in the Konkan region and bordering the Arabian Sea.

Registration apparently started March 8, 2008. This year publicity is currently sparse, so much information emanates from a Technical Blog called Jalaj.net. Revisit it during the next month, for further details.

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Scrabulous On Sudoku

Scrabulous On Sudoku

Based on the March 2, 2008 New York Times Article about the dilemmas posed by Scrabulous™, an online game invented by Rajat and Jayant Agarwalla, from Kolkata, India, this cartoon was born.

The online game appears to be an intimate embrace of Scrabble™, currently physically sold and distributed by Hasbro, Inc. and Mattel Inc., who together divide up the World Rights to sell the game.

As is becoming clearer in the 21st century, having an online version stimulates sales of physical (original) versions. By squelching the online versions, these companies risk severe sales reductions due to bad publicity and a collective vow to boycott those company products. By not squelching the online versions, the companies must adapt (like the music and movie industries are [not] doing) or go out of business anyway. Choose wisely.

I thought it would be amusing to mashup Sudoku with Scrabulous. You can play it with either game goal in mind, but pursuing both will no doubt mentally bifurcate you, which is a serious condition, sometimes leading to split personalities.

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Eye Chart Sudoku

Eye Chart Sudoku

Have you ever been to the Eye Doctor (Optician, Opthalmic Dispenser) and got tested for your visual acuity and thought: “This test is too easy!” ? I have. The result is this cartoon. I heartily recommend it to all who have to get their vision checked. Try to talk your doctor into using this chart rather than his. You may both be surprised at the results. Consider it a Vision Quest.

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Spider Sudoku

Spider Sudoku

While escorting a spider out to the back yard, I mused about how spiders might solve Sudoku puzzles. This is the result. It relates to the party game of Twister patented by Charles F. Foley and Neil W. Rabens in 1966 and originally sold in the United States by Milton Bradley Company.

According to Torsten Sillke, The original inventor, Reyn Guyer, designed a Polka Dot Mat For store display purposes, but later converted it into a game and called it “Pretzel”. Currently, Hasbro Toys which took over Milton Bradley in 1984 sells the game.

I imagine that Spiders “instinctively” solve the puzzle, given the various starting numbers by transitioning from all instances of one value ( such as an 8 ) to all instances of the next value chosen. This is rather unlike humans, who use logic and solve by rows, columns and blocks.

The underlying (!) puzzle is considered hard, but may be made easier by taking the spider’s hints.

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Ripple Effect Sudoku

Ripple Effect Sudoku

This Puzzle uses various sized grids to fit sets of pentominos within. I’ve chosen a 9×9 grid. I think the name, Ripple Effect is suggestive of bigger integers making a bigger splash given their unneighborliness in the rule set. There are no tip sheets as yet, although a strategy may be like that of Paint By Numbers, where you have to account for not only where candidate numbers could be, but also where they cannot be. Ripple Effect was created by Nikoli in 1998.

There are some sites with Ripple Effect Puzzles:

You Play.com, an online puzzle site with free and paid memberships. Getting a free membership is a chore, if not impossible. The form decided my email address was already in use and rejected its association with a new userid! Clicking on Account details made no impression on the script.

Online Puzzle Ripple Effect has multiple puzzles of sizes 8 x 8, 10 x 10, 18 x 10 and 24 x 14.

Ewe Weidemann’s Sudoku Variants Page.
This site has a huge number of Sudoku and other Puzzle variants well organized, although mostly one example of each kind.

I may have to acquire some Nikoli published puzzle books on this variant.

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Mayan Sudoku

Mayan Sudoku

In only a few more years, by December, 21, 2012, that year’s Winter Solstice, the Mayan Calendar (Long Count) will be completed. See “The How And Why Of The Mayan End Date In 2012 A.D.” by John Major Jenkins. It has been keeping track for the last 5125.36 years, since August 11, 3114 B.C. From the accuracy of the Calendar, myths of the end of the world with the end of the calendar have emerged. So the next 5 years will be quite interesting.

The site Mayan Numbers is the reference for Mayan numbers and their names.

There is a Mayan to Arabic Number converter located in The Mayan Astronomy Page.

Some information about the history of Mayan numbers is given in Mayan Mathematics page

A general introduction to Mayan numerals is located in Mayan Numerals.

It is fascinating to “try on” the various (obscure) number systems and other representations of the digits 1-9 while playing a Sudoku that is not difficult but not easy either.

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Repeat-Letter(s) Sudoku

Repeat-Letter(s) Sudoku

A (Mensa!) Puzzle Book by Walter Mackay called Repeat-Letter Sudoku caught my eye this week.

This book offers puzzles where there is one (or more) doubled letter(s). In the Cartoon, there are two repeated letters: U and A. No matter. Just do the Sudoku Puzzle as usual and treat each of the pair as two different numbers.

It may help to write the same letters in unique ways: one in block letters and one in cursive or lower case. Alternatively, you can just keep count in every row, column, and block that duplicated letters show up exactly twice.

I like the effect of the no duplicates rule in the original sudoku being relaxed. It forces me to look anew at the puzzle and how it can be done, without prior built up procedural blinders. Interestingly enough, this particular variant appears studiously ignored by the rest of the internet.

I suppose if this carried far enough, it becomes simple to solve (e.g. All but one letter is duplicated 8 times). Don’t do too many of these; you may have to complain to your Eye Doctor that you’re seeing double!

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Boggle Sudoku

Boggle Sudoku

Safe shaking occurs when you envelop the board in loosely wrapped Plastic Wrap. Naturally, the idea is to have the displayed letters (in any orientation) occur in each row, column and block of 9 cells. The cartoon shows a failed attempt. As an added bonus, once you’ve come upon the solution, you can look for small words in the language of your choice occuring contiguously left (backward), or right (forward) or up or down or diagonally.

The game Boggle (TM) was invented by Allan Turoff and usually comes in a 4 x 4 grid. Larger Boggle games use a 5 x 5 grid. There is also a children’s version of Boggle as well as a travel version. See Wikipedia for details.

I’ve gotten some feedback during last week and I am happy to report that the Website for color sudoku puzzles, mentioned last February, 2007, which was called Brainfreeze Puzzles is no longer “frozen”. The site has been revamped; Philip Riley and Laura Taalman’s Color Sudoku book was published in mid-2007.

Look for the Published Puzzles link for free puzzle variations. There are also tutorials for the Sudoku variants. An original innovation is the Bold X variant, with 6 diagonals, 2 main diagonals and 4 “subprime” neighboring diagonals, which have non-repeating digits as well (just not all the numbers).

I’m glad the site is active again. It is a treasure trove of color and variants.

Another viewer simply named Maff, from the United Kingdom, observed that all of the variants that have been shown in this Blog are by and large based on a 9 x 9 Sudoku Grid. This of course is not an accident, since the subtext of the blog is to demonstrate the vast utility of Power (squared) Sudoku White Boards and clipboards, even if (or when) you tire of the original Sudoku puzzle and seek to recapture that old excitement via variations.

Maff has a site called Sudoku Evolution which has created and displays Sudoku variants where the board size is a variable. The site offers a monthly magazine, eBooks, including a free sample pdf file, in which you can modify the file to save or reset your solution entries, as well as print the original puzzle.

The rules for each variant are depicted as graphical animations in an easy and clear manner. Despite there being a few broken links in some of the larger sized 2-D and 3-D puzzles, I plan to spend some time on these kinds of variants. Thanks for letting me know about this site, Maff!

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Crop Circles Sudoku

Crop Circles Sudoku

So as I was waiting for my Toyota Matrix (dashboard view) to be serviced, I was reading fairly metaphysical Book called 2012, The Return of Quetzalcoatl, by Daniel Pinchbeck. who spends some time discussing people who take crop circles seriously. Note the cover art.

It occurred to me that because there have been so many instances of crop circle manifestations, especially in the United Kingdom, that the sheer precision and incuse designs would provide clear examples of geometric one-to-one correspondences with the first 9 digits. Clearly, if aliens are trying to communicate with humanity, using geometric art as the communication medium offers a common reality that beats the symbols we use for our number system(s).

I am indebted to Lucy Pringle’s Crop Circle Photographic Library for these images. Her collection of photographs of these mysterious, aerial views of crops bent artistically is extraordinary.

She is a leading researcher and author of 3 books on the subject — Crop Circles: Greatest Mystery of Modern Times (2000), Crop Circles (2004), and her latest Crop Circles: Art in the Landscape (2007).

I hope this cartoon helps to publicize her efforts to bring serious attention to all humanity (who’s interested) in this curiously ignored, yet significant messaging system between an unknown entity or entities and humanity.

I wish a happy new year to all, worldwide. Whenever you’re ready.