If you’re interested in sudoku, come along to the official UK sudoku championship next weekend, the 29th-30th of March, at Selsdon Park Hotel just south of London, outside Croydon. There’s full details on the UK Puzzle Association site. There’s still spaces available.
Mind you, it’s not just sudoku – there’s also the UK puzzle championship taking place the same weekend, and there’s a low price which includes overnight accommodation and most meals for those who take part. Winners of both events get the chance to represent the UK in the World Puzzle Championships and World Sudoku Championships.
One of the puzzles in the sudoku part of the tournament is Product Killer Sudoku, a variant on Killer Sudoku where multiplication, rather than addition, is used.
So: just place 1 to 9 once each into every row, column and bold-lined box. Also place numbers in each dash-lined cage so they multiply to the given total. You also can’t repeat a number within a dashed-line cage.
A quick heart-shaped sudoku for Valentine’s Day. Just place 1 to 9 once each in every row, column and bold-lined box.
I’m incredibly excited to announce Brained Up, a cutting-edge brain training site that will help you do just that – upgrade your brain! It’s based around daily online sessions that each provide a wide-ranging mental workout. The site launched just before Christmas, and already has a healthy number of daily users.
Using Brained Up, just a few minutes a day is all it takes to upgrade your brain. The site constructs a personalized training plan for every user, optimized to get the best out of your body’s most important organ. Every schedule includes a wide range of brain games, ensuring full coverage of key mental skills – as well as keeping it fun throughout.
Studies have shown that suitable brain training activity can make you quicker and smarter, which can lead to improved creative, conversational and social skills. Brained Up therefore features scientifically designed exercises, based on extensive research, to help ensure comprehensive coverage of key cognitive skills, including creativity.
It’s at www.BrainedUp.com.
Sudoku Xtra 24 is now finally available! It’s packed with 130 puzzles of a wide range of types, including a huge variety of sudoku variants.
This issue I’ve included some new sudoku types such as Two-grid Interconnected Sudoku, Mystery Multiple Sudoku and Blackout Sudoku. I’ve also made an effort to include all of the most popular variants as requested by readers, such as Consecutive Sudoku, Inequality Sudoku, Odd/Even Sudoku – and of course many more.
There’s also a range of non-sudoku puzzles, including Light-up/Akari, Hashi, Slitherlink, Battleships, Skyscrapers, Calcudoku, Futoshiki, No Four in a Row, and more!
It’s available either as a PDF to print yourself (every page is self-contained, so you can print only the pages you want), or as a professionally-printed book direct from Amazon – there are links for all of these on the Sudoku Xtra site.
I made this puzzle just before Christmas, and it’s been waiting on my desktop to be posted here ever since! Well, now it finally has been.
This is a Sum Skyscraper. Place the digits 1 to 5 once each into every row and column in the grid. Numbers outside the grid provide the total (i.e. sum) of ‘visible’ grid digits along that row or column, if you imagine each digit as a building of that many storeys. Taller buildings always obscure shorter ones. So, for example, a clue for 21354 from the top of such a column would be 10, since the 2, 3 and 5 are visible (the 1 and 4 are obscured by the 2 and 5 respectively), and 2+3+5 = 10.
A Sudoku, in a star shape.
Just that. (Place 1-9 once each into every row, column and bold-lined 3×3 box).
I’ve recently been making some material for a book of kids’ mazes, and so I thought it would be fun to post a harder version of some of those puzzles here.
First-up, here’s a weave maze, so-called because the paths weave over and under each other. In this puzzle I’ve drawn narrow bridges where one path crosses over another.
If the first one is too easy for you, try the second! It needs to be printed full-page in order to have enough space to solve it.
Just enter at the top of the maze and follow paths until you exit at the bottom of the maze.
I’ve recently launched a new series of ‘101 Giant Sudoku’ books, to cater for those who like their Sudoku to be considerably larger than normal!
You can see the entire series at PuzzleBooks.org (scroll to the bottom) or visit Amazon and search for “101 giant sudoku”.
There are currently 12 books in the series: 14×14, 15×15, 16×16, 18×18, 20×20, 21×21, 22×22, 24×24, 25×25, 28×28, 30×30 and 36×36.
The larger puzzles work just as you’d expected, so in Sudoku 36×36, for example, you must place 0-9 and A-Z into every one of the 36 rows, 36 columns and 36 6×6 boxes!
These puzzles are designed so they don’t need any advanced logic – just scan the rows and columns and boxes to see what’s missing and what can fit where.
All of the puzzles are designed with attractive 8-way symmetry patterns.
Following-up yesterday’s Skyscraper puzzles, I thought I’d post a couple of Sum Skyscraper variant puzzles.
Sum Skyscraper puzzles are very similar to Skyscraper puzzles, so no number can repeat in any row or column and external ’skyscraper’ clues reveal information about the numbers in the main grid. In 5×5 puzzles place 1-5, and in 6×6 puzzles place 1-6.
Each number in the completed grid represents a building of that many storeys, and place the buildings in such a way that each given number outside the grid represents the sum of the number of buildings that can be seen from that point, looking only at that number’s row or column. A building with a higher value always obscures a building with a lower value, while a building with a lower value never obscures a building with a higher value. So the clue ‘6′ in a 5×5 puzzle would indicate that the buildings ‘1′ and ‘5′ can be seen (’5′ is always visible in 5×5 puzzles), so the solution to a row might be 15234.