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2025-12-04

Christmas card 2025

Showing all comments about the post Christmas card 2025. To return to the blog post, click here.

Comments

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

2026-01-18

Will you be posting solutions? I have what is to me an acceptable answer but I think I might be missing a couple of squares

Ewan Leeming

2025-12-30

@Ahmad: Nothing missing, it's written correctly

Matthew

×1

2025-12-30

Is there “three-digit” missing from Q6

Ahmad

×1

⭐ top comment (2025-12-24) ⭐

Thanks again for an advent full of brain teasers. Merry Christmas!

Gert-Jan

×2

2025-12-21

@Matthew, small typo in todays example, bottom left string should be BBBA I feel.

Bob

2025-12-18

@Alec: Yes, it should say positive integers

Matthew

×1

2025-12-18

Is there a word missing (positive?) from Q9? Surely any positive integer, n, can be written as the sum of the consecutive integers -(n-1),...,-1,0,1,...,n-1,n.

Alec

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