Logic Masters Deutschland e.V.

am 1. Dezember 2021, 22:00 Uhr von abecede
Lovely little thing. Thank you DiMono! My only problem was penpa, so I created a penpa+ version (with answer check) where typing in numbers is also a lot more user friendly. See https://git.io/JMoD6

am 15. Oktober 2020, 17:07 Uhr von Willy Wonka
A 3 star difficultly puzzle for me... until I read the rules again and found the word "unique"! A very lovely little puzzle

@Willy Wonka Thanks for taking it on!

am 13. August 2020, 16:14 Uhr von wkossen
lovely puzzle. took me a while to get my head around how to solve it. should have a higher rating!

am 31. Juli 2020, 02:14 Uhr von SudokuExplorer
@uvo I strongly agree with you. Especially when you want to talk about unique prime factorisation. I would consider 1 (and -1) to be the units of the ring of integers.

am 31. Juli 2020, 00:20 Uhr von uvo
1 is not a prime. Any "definition" that says otherwise is wrong.

am 30. Juli 2020, 23:48 Uhr von Naantje
It's probably best to mention in the rules that you don't consider 1 a prime number, because according to some definitions 1 does qualify as a prime. (Oh, the debates I've had over the years!) At least two possible solutions if you consider 1 a prime.

@Naantje A prime number is defined as having exactly two divisors: 1 and itself. The number 1 only has 1 divisor. Therefor, by definition, 1 is not prime. It has nothing to do with my opinion, it is objective fact.

@DiMono: By the definition you were taught, but not everyone is taught that definition, some people aren't taught the "exactly two divisors" part... I think by this point it's pretty clear that many people are making the mistake of counting 1 as prime and it's not a logic problem, it's a problem of unclear definitions. I remember several teachers who included 1 on the list of primes... I just think clarification in the rules would make the puzzle more enjoyable.

am 14. Juli 2020, 02:57 Uhr von DiMono
I suspect one reason for the difficulty being rated 1-star is the simple fact that it is a 4x4 puzzle. 4x4 puzzles are by their nature significantly easier than their larger counterparts, so it's not unexpected for any 4x4 to have an easier rating by consensus, regardless of how hard it is compared to other 4x4 grids.

Personally, I think it's a 2-star 4x4 puzzle, but the setter does not get to decide how hard the solvers find it. It is what it is. :)

am 13. Juli 2020, 23:53 Uhr von glum_hippo
There are comments where people reveal that they got tripped up by some of the rules, but that’s not the same as having difficulty. The rating system involves a heavy amount of subjectivity. For my part, even if I struggle with a puzzle I might give it an ‘easy’ rating if, in retrospect, the logic seems fairly straightforward.

am 13. Juli 2020, 23:21 Uhr von uvo
"Wrong" implies there is an objective "Right", which I don't think is true at all.

am 13. Juli 2020, 23:17 Uhr von henrypijames
@uvo: I understand the mechanism. I'm saying judging by additional empirical data, those 1 star votes are wrong.

am 13. Juli 2020, 11:55 Uhr von uvo
The difficulty is calculated simply as average of everyone's votes. If it is shown as one star then because enough solvers voted one star.

(There is some bias because someone who didn't solve a puzzle is not eligible to vote, but I don't think that makes much of a difference in this puzzle.)

am 11. Juli 2020, 14:44 Uhr von henrypijames
Not only is this puzzle underrated, but the difficulty level should be higher than 1 star as well, considering how many people are admitting to not being able to solve it straightforwardly (myself included).

am 11. Juli 2020, 01:55 Uhr von DiMono
Updated German text to be more clear.

am 11. Juli 2020, 00:12 Uhr von glum_hippo
Oder 'eine verschiedene Primzahl' perhaps

am 10. Juli 2020, 23:35 Uhr von olima
Please clarify in the German version that every killer sum appears only once (which seems to be the intention, right?). (Jeder Käfig ergibt eine nur einmal vorkommende Primzahl als Summe.)

I didn't realize the German was not descriptive enough. I have updated the text. Thank you for bringing it to my attention.

am 10. Juli 2020, 21:14 Uhr von glum_hippo
1 is not a prime number. The prime numbers that could possibly appear in this puzzle are the following: 2,3,5,7,11,13,17

am 8. Juli 2020, 22:46 Uhr von SKORP17
Ich bin auch darüber gestolpert, es gibt eine Zahl, bei der man nicht denkt, dass es eine Primzahl ist.

am 8. Juli 2020, 19:38 Uhr von Saskia
Thanks a lot! Have to try again :-)

am 8. Juli 2020, 19:12 Uhr von henrypijames
I agree: This puzzle absolutely deserve a higher rating - so simple yet so pure its logical path.

am 8. Juli 2020, 14:49 Uhr von ffricke
Sehr schöne Idee

am 7. Juli 2020, 19:24 Uhr von Rollo
@Saskia: Nein. Du hast zwei gleiche Primzahlen.

am 6. Juli 2020, 22:35 Uhr von uvo
Die schlechte Bewertung kann ich überhaupt nicht nachvollziehen.