Friday Puzzle #141 - The Art of Sudoku - Sample #2

[motris]

This past weekend I finished constructing all the puzzles in my forthcoming classic sudoku book: The Art of Sudoku. I now have a first draft of the book laid out, but still need to check some timings, make cover art, and do other small fixes. But my Spring target will certainly be met. I wanted to share another sample puzzle from this book (see

Comments

[ext_209009]

Well done. This approach to construction, with a pivotal innovative step to enjoy puzzling out, is what I look for and enjoy the most for any type of puzzle. The fact that it's done so rarely with sudoku is one big reason why it's not a favorite type of mine.

Was it perhaps intended and/or forced that the digits crucial to the "just one cell" step were the very last ones to get filled in?

[motris]

Not forced, but some row/column rearrangement from the first draft ensured the critical set-up was not just in the givens. You can encounter puzzles like this from the best Japanese nanpure magazines, but not too many other spots.

[figonometry]

Very nice. It always astounds me when you manage to hit the sweet spot between "having an interesting break-in" and "destroying the break-in by adding the rest of the givens".

However, I don't get where the 'just one cell' was supposed to come in. My big break-in (after filling in the non-given givens) was a naked triple following a naked double.

[motris]

Spoiler: So the puzzle is built around getting a digit in R1C8. Everything that comes after that digit is just an 81-cell solution. In the old format, R1C8 would have been the answer.

[ext_1094477]

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