Latest letter
The digit with one square
Saturday's Master called for it seventeen times. Here is how to find it.
Read the latestThe weekly letter
From Claire's Desk
One solving technique explained properly, news from the wider sudoku world, and what changed in Claire's Sudoku.
Past letters
RSS feedSeventeen is the floor
How the smallest possible sudoku was settled, and a smaller rule you can prove with a pencil.
Read the letterA line claims a box
The mirror of last week's move, worked on Wednesday's No. 72.
Read the letterA box points to a line
International Sudoku Day's edition, and the move Saturday's Master needed.
Read the letterThe first world champion
Lucca in 2006, a hidden pair worth learning, and what Saturday is for.
Read the letterHow a naked pair clears a row
A worked example with real coordinates, plus this week's seven editions.
Read the letterDelivered weekly
Get the next letter by email.
Join the same newsletter that powers this archive. One useful note at a time, with a clear unsubscribe link in every email.