Sudoku Graduation, 2023

Changes are in the air!  May is graduation for some colleges and universities, so we will celebrate your graduation from a Sudoku undergrad to graduate student!

If you have been following my articles, you know that for over 6 years I have been providing step-by-step instruction for solving the “feature” puzzle.  That officially ends with this article.  However, I will provide a clue for the feature puzzle, with a hint such as to Step 5 or 6 required, along with a reference to a previous puzzle where the exercise is explained in detail.  Then all you have to do is click on that previous article and review the technique.  

Also, I will not be providing the answer to the puzzle.  Showing the specific answer is not necessary as you either get it right (no repetition of numbers 1-9 in a row, column or box), or you do not.  If you do not, you have the choice of starting the puzzle over.

Clueless?


We start with a Sudoku puzzle in progress, where it appears that there are no more obvious or not-so-obvious clues.  Can you find the hidden clue in Puzzle #149?

Puzzle #149

(The answer follows the conclusion of Puzzle #152, the feature puzzle for this month)

Simply a Logic Puzzle

Difficult rating … 6/10
(Rating based on puzzles not requiring advanced techniques)

Puzzle #150

Impossible to solve?

Impossible?  No.  Difficult?  Extremely.   Puzzle #151 will be challenge for you.

Advanced Techniques (Steps 6 and/or 7) are required.  Difficult rating 6/10.

Puzzle #151

Feature Puzzle

Difficult rating … 2 /10
(Rating based on puzzles requiring advanced techniques)

PUZZLE #152

PREPARATION

Prior to utilizing techniques 1-8, complete the 5 Steps of Puzzle Preparation …

  1. FILL IN DATA FROM OBSERVATIONS
  2. FILL IN OBVIOUS ANSWERS
  3. FILL IN NOT-SO-OBVIOUS ANSWERS
  4. MARK UNSOLVED CELLS WITH OPTIONS THAT CANNOT EXIST IN THOSE CELLS
  5. FILL IN THE OPTIONS FOR THE UNSOLVED CELLS
    (hint … If you need a refresher on Step 6, please click the April 2023 issue)

[Clue for Puzzle #149 …  did you find the clue?  If not, read on.  Check the contents of row 4 and box 5.  What do you see?  The three given numbers in row 4 and the three given numbers in box 5 are not the same.  Therefore C4R4, C5R4 & C6R4 can only be three numbers, in this case, numbers 1, 2 & 4.  This means those three cells form a triplet.  Then, note that in row 4 the re-maining cells are limited to options 2, 7 & 9.  In column 8 a 2 & 7 already exist; therefore, C8R4=9.  You may want to finish solving this puzzle.  The advance techniques (6 & 7) are not required.
This situation appears more often than you might imagine when solving Sudoku puzzles.  So put this one in your tool bag.]

May the gentle winds of Sudoku be at your back,

By Dan LeKander

Important Editor's Note

Hey there... do you know how daunting it is to type Puzzles #149,#150, #151, &#152?  Yes, Dan Lekander has produced over 150 Sudoku puzzles for us and better still he has taught us how to solve them. This issue is slightly difference. So, Dan would like to hear more from his readers, such as questions, comments & suggestions - info@thousandislandslife.com.  We will forward this to Dan, and he will contact you directly.  Thank you."

Recently someone wrote to ask how to fill them out online. Unfortunately, you need to print them yourself,  but that is easy to do and I know you will have just as much fun. Also you can use a grid sheet and copy numbers onto the grid.

And, if you have not already done so, I suggest you purchase Dan’s book: “3 Advanced Sudoku Techniques, That Will Change Your Game Forever!” Purchase of a book includes a 50-page blank grid pad, 33 black and two green tokens. The book is available by contacting info@thousandislandslife.com.

Be sure to read the TI Life's review of Dan's book by Jesse Kahn published in Jun 2015.

Here are links to all past Sudoku Puzzle Challenge beginning: February 2016, March 2016, April 2016, May 2016, June 2016, July 2016, August 2016, September 2016, October 2016, November 2016, December 2016, January 2017, February 2017, March 2017, April 2017, May 2017, June 2017, July 2017, August 2017, September 2017, October 2017, November 2017, December 2017, January 2018, February 2018, March 2018, April 2018, May 2018, June 2018, July 2018, August 2018, September 2018, October 2018, November 2018, December 2018, January 2019, February 2019, March 2019, April 2019, May 2019, June 2019, July 2019, August 2019, September 2019, October 2019, November 2019, December 2019, January 2020, February 2020, April 2020, May 2020,  June 2020 and July 2020, August 2020,  September 2020, October 2020, November 2020 and December 2020, January 2021, February 2021, March 2021, April 2021, May 2021, June 2021, July 2021 , August 2021, September 2021 ,  October 2021, November 2021, December 2021, January 2022, February 2022, March 2022, April 2022 , May 2022, June 2022, July 2022 , August 2022, September 2022, October 2022, November 2022, December 2022, January 2023, February 2023, March 2023 & April 2023.