Coordinators
(Published on 6. November 2025, 21:41 by mathpesto)
Rules:
Normal sudoku rules apply.
Coordinators: There is exactly one "coordinator" cell in each row, column, and box. The value of each coordinator cell is the sum of its row number and column number (e.g. if R3C5 is a coordinator cell, the value is 8, regardless of the digit placed in R3C5). Each digit appears in a coordinator cell exactly once.
Thermometers: Values along a thermometer increase from the bulb to the end.
Arrows: Values on an arrow sum to the value in the corresponding circle.
Solve online:
Solution code: Digit in coordinator cell in Row 1, then Row 2, etc. (9 digits)
Comments
on 12. November 2025, 17:47 by War
3* difficulty, great puzzle!
on 8. November 2025, 18:41 by Florian Wortmann
Very enjoyable :-)
on 8. November 2025, 18:41 by ICHTUES
Very enjoyable :-)
on 7. November 2025, 18:04 by ketchup_monster
Extremely fun puzzle, I think I spotted some neat tricks which made it slightly easier, but thoroughly enjoyable throughout
on 7. November 2025, 15:06 by GeorgeTheToad2
Very well put together and some lovely logic. Approachable and fun too. Thank you.
on 7. November 2025, 10:33 by damo_89
Tricky mid solve as I discovered when I made an invalid leap and broke the puzzle, but always fair. Lovely stuff.
on 7. November 2025, 10:11 by Snookerfan
Very nice! Mid solve was quite hard, so 4 stars seems reasonable. Enjoyable solve, thanks!
on 7. November 2025, 09:57 by Bankey
Fun puzzle. Thanks, @ mathpesto :).
on 7. November 2025, 00:17 by mathpesto
Clarified rules
on 7. November 2025, 00:11 by lmdemasi
Rule should say something like: The value of each coordinator cell is the sum of its row number and column number.
-----
Thanks that's much better! I will change it shortly.
-Math Pesto
on 6. November 2025, 23:48 by Wgrady3
I would love to attempt this puzzle but the rules are unclear. The way the rules read you could never place a coordinated 1 in the puzzle as R1C1 would equal 2. Also how could you place any coordinated number in box 9 as the lowest is R7C7 which by the rules would be 14. Please clarify the rule set and I’ll attempt
------
Sorry the rules were unclear. The actual digit in a coordinator cell has no impact on that cell's value. So if R9C6 is a coordinator cell, its value is 15 regardless of the digit it contains, and the cells along that arrow must therefore sum to 15.
-Math Pesto
on 6. November 2025, 23:30 by collin525
rules need explanation. To me it seems as if digit 1 can never be coordinated and R1C2=R2C1
------
Sorry the rules were unclear. The actual digit in a coordinator cell has no impact on that cell's value. So if R9C6 is a coordinator cell, its value is 15 regardless of the digit it contains, and the cells along that arrow must therefore sum to 15.
-Math Pesto
