Easy Peasy Sudoku Advent (22) - Summing Up
(Published on 22. December 2025, 06:00 by Richard)
This sudoku advent calendar contains 24 variants that were included in my Sudoku Variants Series (SVS) but turned out to be too hard to be solved by a wide range of puzzlers. I aim for difficulties of 1-2 stars and have written some general and/or specific hints as well. I hope some players will try the original SVS puzzle #315 after solving the advent version.
Summing Up
General hint for this type:
This type can be treated as a sum skyscraper sudoku, but with a connected chain of increasing digits. Or the sum of the digits on a thermometer somewhere in the corresponding row or column.
Filling column 4 is obvious and after that, the sum of 36 in R9 can only be reached in one way.
Apply classic sudoku rules.
Clues outside the grid indicate the maximum sum of a group of connected ascending digits from that side in the respective row or column.
And after that, there is also only one possibility for the 10-clue on the other side of that row...
Sudokupad (no answer check)
Sudokupad (with answer check)
or
Penpa+.
Solution code: Row 5
Comments
on 23. December 2025, 01:17 by dzamie
Interesting rule! Can't say I'm a fan of solving it (felt like a lot of back-and-forth with a killer calculator to keep track of possibilities), but once finished, it's rather pleasant to see.
on 22. December 2025, 10:18 by SennyK
Another great entry to the series :-) I feel you Piatato, tricky Richard gave us automatically resolved clue just so that we forget its symmetrical twin!
on 22. December 2025, 10:08 by Piatato
Very nice! I kept forgetting one option for a clue, but luckily I noticed my silly assumption on my third try. Very smooth and fun!
