Rules:
Euler Square: Each cell contains one of the digits 1, 2, 3, 4, or 5, and one of the colors red, orange, yellow, green, or blue. Digits/colors may not repeat within a row/column. Each possible combination of digit/color within a cell must appear exactly once.
Palindromes: The two red lines are color palindromes and the two gray lines are number palindromes.
Quads: Digits/colors within a circle must each appear at least once within the four surrounding cells.
Solve online:
Lösungscode: Digits in column 1 followed by first letter of each color in column 1 (top to bottom) (e.g. 21435BYOGR)
Gestern, 18:58 Uhr von ofsmul
Agree with Snaques - hardest part is figuring out how to mark! I finished the puzzle, then needed to work out which of my colors was actually red, green, etc. for the solution code. :)
Gestern, 13:22 Uhr von RockyRoer
A few years ago I had done an Euler square before and told myself "Never Again!". I'm glad I didn't listen to myself. Thanks for sharing!
Gestern, 13:19 Uhr von RockyRoer
A few years ago I had done an Euler square before and told myself "Never Again!". I'm glad I didn't listen to myself. Thanks for sharing!
Gestern, 12:53 Uhr von Snaques
The biggest challenge with these is how to mark everything. Otherwise really fun and not too difficult puzzle.
It almost felt like I had to do the puzzle twice the way it worked out in the end.
am 12. Juli 2026, 06:48 Uhr von Crusader175
Fun puzzle!
am 12. Juli 2026, 02:32 Uhr von Exigus
Very cool combo, thanks!
am 12. Juli 2026, 00:50 Uhr von Voidslime
Wow i can’t believe how friendly and smooth this puzzle is for how intimidating the rules are
am 11. Juli 2026, 18:35 Uhr von jubengo
First time doing a ruleset like this. It was wonderful :)
am 11. Juli 2026, 14:09 Uhr von Snookerfan
Perfect combination of interesting and appraochable, thanks!
am 11. Juli 2026, 11:51 Uhr von Kirra
That made me think. Quite fun