**SUDOKU WEEKLY—SUDOKU MONTHLY—SUDOKU QUARTERLY**

**contains a Sudoku for each day of the week. Sudoku weekly is only available as a downloadable and printable pdf file. Downloads are for free.**

*Sudoku weekly*On Monday a regular Sudoku has to be solved. On other days other kinds are included:

*Magic Sudoku’s*: the gray blocks are magic squares: Each row and each column of a block adds to 15 and all nine digits occur. Each week, there are five of this kind.

On Thursday you will find a

*Diagonal Sudoku*: in the solution, the diagonals should contain all digits 1 to 9.

A sample of *Sudoku weekly* can be borrowed from the (Dutch) public library.

** Sudoku monthly** consists of the five Sudoku weekly’s overlapping the current month. Sudoku monthly of March, 2017 is now available at Bruna. The May, June and July issues of 2016 are still available, too. Sudoku Monthly costs € 1.75.

You can subscribe to Sudoku monthly (€ 17.50) to obtain all Sudoku Monthly’s of 2017. Use the order form below.

* Sudoku quarterly *consists

*of the 13 Sudoku weekly’s of the present quarter and costs € 4.95. The fourth quarter of 2016 is available at AKO’s. The first quarter of 2017 will appear shortly.*

**Background**

The Sudoku’s are generated using a computer program written in the programming language of the statistical package** R**. The results are written to LaTeX files which can readily be printed in the proper layout. The system was developed by Herman Adèr.

At first, the magic Sudokus in Sudoku weekly only contained at most three magic blocks, but full-magic Sudokus, in which each block is magic, are now also included. Recently, we extended the system so that it can generate Ritmeester Sudoku’s (named after Peter Ritmeester), which have four extra blocks shifted to the middle. We have now offer new types of Sudoku’s in which two magic Ritmeester blocks appear. It can be proven that full magic Ritmeesters are impossible.

**DOWNLOADABLE**

Sudoku weekly (Week 13, 2017)

Borrow from the public library

**SUDOKU MONTHLTY**

**SUDOKU QUARTERLY**

Third quarter (2016)Fourth quarter (2016)

**SUBSCRIPTION**

* For more information: see the website:* www.jvank.nl/Sudokus