4 Color Theorem

(Published on 30. June 2025, 03:15 by eap314)

4x4 sudoku rules apply to each grid.
Each color contains a digit that is the same throughout the grid. Colors are not necessarily distinct.

Play on Sudokupad

Not as beautiful as before, but a good introduction to meta-logic.

Solution code: Gray row 4 (4 digits)

Solved by zonny, atmospherium, mathpesto, taco.bella, rjhwm3, HazelTheColor, APigthatflys, Mattisahuman, buttons, Fizz, fuxia, jalebc, residentholy3, saxdaddyj, RickiFerrara, Decapod, NEWS, Avron, ... kangaroo, Derek, Leaving Leaves, The Book Wyrm, NXTMaster, JTurnquest, ManuH, webato, Blake Saligia, MTFlowCzq, FireTruckFuel, geronimo92, ElecCatMon, EnotiAndy, jessisstressed, Laje6, Redcapped

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Comments

on 29. December 2025, 23:19 by geronimo92
Colors ARE necessarily distinct.... by sudoku looking at all 4 puzzles !!

Last changed on 1. July 2025, 19:45

on 1. July 2025, 19:10 by dzamie
Sudokupad conflict checker is a little buggy on this one. Luckily that's not much of a big deal in 4x4s, since everything's right there and very easily visible. Fun little puzzle!
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eap314: It was built from a 9x9 grid, so it probably thinks it's a 9x9.

on 1. July 2025, 00:59 by SanFranSam
Speaking of the four colour problem... have you ever been to Kentucky? ;)

Last changed on 30. June 2025, 16:17

on 30. June 2025, 15:56 by Pairot
Colours are not necessarily distinct, but they don't necessarily overlap either!
Got a good chuckle out of me, great puzzle.
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eap314: If you know what the 4 color theorem is, it's even more funny. I'll leave this visible as a hint

on 30. June 2025, 10:45 by Fisherman
Very enjoyable.