Blog address : http://tcollyer.blogspot.com/
Owner : Tom Collyer

Link to original post : Friday Puzzles #262

So Consecutive Sudoku really annoys me because it always ends up solving as non-consecutive Sudoku - and any really cool combinatorial tricks end up being drowned out by the non-consecutive logic.

I believe it was Bastien who first introduced the idea of a Consecutive pair to the Daily League, and it's a really good idea.  I was quite tempted to stick with the ubiquitous bar notation for this puzzle in an attempt to reclaim it, but I will stick with what Bastien used for now.  Marked pairs of adjacent cells must contain consecutive numbers; there is no restriction on adjacent cells with no marking.  Enjoy!

    #301 Consecutive Pair Sudoku – rated medium

All puzzles © Tom Collyer 2009-15.


Posted in Daily League, Friday Puzzles, Medium, Sudoku Variants

Link to original post : Friday Puzzles #263

Fairly recently I had the honour of being asked to be one of Roland Voigt's weekly "experts " for his daily skyscraper puzzle project.  I am always in awe of anyone who tries to maintain any sort of daily puzzle project for any period of time, and this one is of particular note because in my opinion Roland is by far and away the world's leading authority on both solving and creating Skyscrapers puzzles.

Please take a look here:

http://www.hochhausigel.de/e-index.html

I think eventually some commentary on my times will appear on Roland's blog - as someone who often struggles with a weekly schedule I am more than happy to be patient on this count!

Anyhow, skyscrapers this week.  Not too hard, not too easy.  Enjoy!

    #302 Skyscrapers – rated medium

All puzzles © Tom Collyer 2009-15.


Posted in Friday Puzzles, Medium, Skyscrapers

Link to original post : The Art of Puzzles: Masyu

Here's a Masyu that appeared over at GM puzzles.  Enjoy!


Posted in Grandmaster Puzzles, Masyu

Link to original post : Friday Puzzles #264

A medium level puzzle, but only just bearing in mind I've never posted a Quadro Sudoku here before.  It's a slightly subtle odd/even style variant, where the solving flow is very much either on or off, so perhaps your enjoyment mileage may vary.  If you struggle, let me reassure you by saying these can get a lot harder!

Rules: No 2x2 block of cells may contain exclusively odd or exclusively even numbers.

Enjoy!

    #303 Quadro Sudoku – rated medium

All puzzles © Tom Collyer 2009-15.


Posted in Daily League, Friday Puzzles, Medium, Sudoku Variants

Link to original post : Friday Puzzles #265

I'm quite pleased with this Even Sudoku puzzle, although admittedly I'm feeling quite tired. Enjoy!

    #304 Even Sudoku – rated medium

All puzzles © Tom Collyer 2009-15.


Posted in Daily League, Friday Puzzles, Medium, Sudoku Variants

Link to original post : Friday Puzzles #266

Here's an easy Masyu. Enjoy!

    #305 Masyu – rated easy

All puzzles © Tom Collyer 2009-15.


Posted in Easy, Friday Puzzles, Masyu

Link to original post : Friday Puzzles #267

Well what do you know, it's not a Friday.  This week's offering is Eliminate Sudoku, a novelty (at least to me!) from the 2014 World Sudoku Championships, where the puzzle was supplied by Ko Okamoto of Japan.  Incidentally if I'm wrong about this and there is an earlier example, then I'd certainly like to be enlightened!  Anyhow, this for me epitomised everything an innovative new variant should be - something which isn't overly contrived or a departure from what the average Joe would know as sudoku, something which compliments the standard sudoku solving logic completely naturally, and something that when you think about it makes you wonder why someone hadn't come up with it before.

The rules are easy enough.  Numbers placed in cells with arrows must not repeat in the corresponding direction.  Enjoy!

    #306 Eliminate Sudoku – rated medium

All puzzles © Tom Collyer 2009-15.


Posted in Daily League, Friday Puzzles, Medium, Sudoku Variants

Link to original post : Friday Puzzles #268

Windoku this week.  Better late than never!

    #307 Windoku – rated medium

All puzzles © Tom Collyer 2009-15.


Posted in Daily League, Friday Puzzles, Medium, Sudoku Variants

Link to original post : Friday Puzzles #269

Palindrome Sudoku this week.  I've now got to rush off to watch some clouds obscure the moon obscuring the sun.  Enjoy!

    #308 Palindrome Sudoku – rated medium

All puzzles © Tom Collyer 2009-15.


Posted in Daily League, Friday Puzzles, Medium, Sudoku Variants

Link to original post : Friday Puzzles #270

Sometimes one needs the hammer to strike the stone to indicate the work is done.  Enjoy!

    #309 Irregular Sudoku – rated medium

All puzzles © Tom Collyer 2009-15.


Posted in Daily League, Friday Puzzles, Medium, Sudoku Variants