Hvordan spille Kropki Sudoku
Hvite prikker = påfølgende sifre; svarte prikker = ett siffer er det dobbelte av det andre
Reglene
Standard Sudoku-regler gjelder: fyll hver rad, kolonne og 3×3-boks med sifrene 1–9, hver forekommer nøyaktig én gang.
Kropki Sudoku plasserer prikker mellom par av tilstøtende celler. En hvit prikk betyr at de to sifrene skiller seg med nøyaktig 1 (påfølgende). En svart prikk betyr at ett siffer er nøyaktig dobbelt så stort som det andre (f.eks. 2 og 4, eller 3 og 6). Der ingen prikk vises, gjelder ingen av betingelsene. Noen Kropki-puslespill bruker den 'negative begrensningen' der fraværet av en prikk garanterer at ingen av betingelsene holder, noe som gir enda mer informasjon.
For hvor denne oppgaven kom fra, hvordan den sammenlignes med relaterte varianter og en strategioppsummering, se vår Kropki Sudoku variantoversikt.
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Hvordan løse Kropki Sudoku
Vanlige spørsmål
Hva er Kropki Sudoku? ▾
Kropki Sudoku is a variant where dots appear between adjacent cells. A black dot means one of the two cells holds exactly double the value of the other. A white dot means the two cells hold consecutive digits (differing by 1). Standard Sudoku rules apply, and crucially: if there is no dot between two adjacent cells, they are guaranteed NOT to be consecutive and NOT to have a double relationship.
What does a black dot mean? ▾
A black dot between two cells means one digit is exactly twice the other. For example: 1&2, 2&4, 3&6, 4&8. Note that 1&2 satisfies both black (1×2=2) and white (|2-1|=1) conditions — in Kropki Sudoku, a black dot is used when only the doubling relationship holds, not the consecutive one, unless specified otherwise.
What does a white dot mean? ▾
A white dot between two cells means the digits differ by exactly 1: they are consecutive. Valid pairs are 1&2, 2&3, 3&4, 4&5, 5&6, 6&7, 7&8, 8&9. The order doesn't matter — either cell can hold the higher or lower digit.
How does the no-dot constraint work? ▾
In standard Kropki Sudoku, every possible black dot and white dot relationship is marked. This means that if no dot appears between two adjacent cells, you can be certain those cells are neither consecutive nor in a 1:2 ratio. This negative information is just as powerful as the positive dot clues.
Is Kropki Sudoku harder than regular Sudoku? ▾
Easy Kropki puzzles are accessible and make excellent teaching tools for the variant. Hard and expert puzzles are significantly more challenging than classic Sudoku because you must simultaneously track dot relationships and the negative no-dot constraint across every pair of adjacent cells.
How long does Kropki Sudoku take to solve? ▾
Easy puzzles take 8–18 minutes. Medium puzzles run 18–35 minutes. Hard puzzles average 35–65 minutes and expert puzzles often exceed 90 minutes. Mastering the no-dot constraint is the key to faster solve times at all levels.