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Comments in green were written by me. Comments in blue were not written by me.

2024-12-25

Could I have some help with puzzle 23. I don't see anything about a 3×3 block. How to arrive at a formula for the number of squares that need colouring?

Reza
on /blog/111

2024-12-25

@Reza: I think he reworded it. As for how to solve it, I didn't find a formula or anything. I just basically used his 5x5 example and extrapolated it. It's much less complex than you think it'll be.

Seth Cohen
on /blog/111

×1

2024-12-27

@Seth Cohen: Thanks Seth, I solved it by looking at the 5×5 picture and thinking harder. Thanks to Matthew for another enjoyable set of puzzles. I look forward to reading the proper solution.

Reza
on /blog/111

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