XV Sudoku
5
9
3
4
3
2
5
1
7
9
4
7
4
3
6
2
5
8
6
3
5
7
4
4
8
7
3
9
3
7
2
8
6
1
3
9
2
8
Fouten
0/3
Score
-
Tijd
00:00
Voortgang0%
Gemakkelijk · XV Sudoku
Wissel moeilijkheidsgraad hierboven ↑
Hoe XV Sudoku te spelen
Standaard Sudoku-regels zijn van toepassing. X tussen twee aangrenzende cellen betekent dat ze optellen tot 10. V betekent dat ze optellen tot 5. Paren zonder markering zijn gegarandeerd niet op te tellen tot 10 of 5.
Volledige gids →
X tussen cellen betekent dat ze optellen tot 10; V betekent dat ze optellen tot 5
XV Sudoku Gemakkelijk
XV Sudoku Gemiddeld
XV Sudoku Moeilijk
XV Sudoku Expert
Wat is XV Sudoku?
XV Sudoku (ook wel Ten-Five Sudoku genoemd) plaatst X- en V-markeringen tussen aangrenzende cellen. Een X betekent dat de twee cellen optellen tot 10; een V betekent dat ze optellen tot 5. Veel XV-puzzels gebruiken de negatieve beperking: de afwezigheid van een markering garandeert dat het paar niet optelt tot 10 of 5. In combinatie met standaard Sudoku levert dit zeer strakke beperkingen op over het hele rooster.
In één oogopslag
| Beperkingstype | Cel Relaties |
| Typische gegeven cijfers | 18–24 |
| Moeilijkheidsbeoordeling | ★★★☆☆ 3/5 |
| Gem. oplossingstijd — Gemakkelijk | 8 min |
| Gem. oplossingstijd — Gemiddeld | 18 min |
| Gem. oplossingstijd — Moeilijk | 35 min |
| Gem. oplossingstijd — Expert | 62 min |
Hoe XV Sudoku op te lossen
| Techniek | Wat het doet | Niveau |
|---|---|---|
| Negative Constraint | Where no X or V appears between adjacent cells, their sum is neither 10 nor 5. This eliminates (1,9), (2,8), (3,7), (4,6) for X and (1,4), (2,3) for V. | Beginner |
| Sum Pair Enumeration | List all digit pairs that sum to 10 (for X) or 5 (for V), then use row/column placement to identify which pair must occupy each marked pair. | Beginner |
| Marker Chain Logic | Multiple consecutive X and V markers in a row form a sum chain — enumerate valid assignments for the entire chain simultaneously. | Gevorderd |
| Box X-Interaction | An X pair forces both digits into specific positions within their shared box, constraining all remaining cells of that box. | Gevorderd |
Gemiddelde Oplossingstijden
Gemakkelijk
8 min
Gemiddeld
18 min
Moeilijk
35 min
Expert
62 min
Veelgestelde Vragen
Wat is XV Sudoku?
XV Sudoku is a variant where X and V symbols appear between adjacent cells. An X marks two cells that sum to 10. A V marks two cells that sum to 5. Standard Sudoku rules apply, and — critically — all X and V relationships are fully marked: if there is no symbol between two adjacent cells, those cells are guaranteed not to sum to either 10 or 5.
What pairs sum to 10 (X)?
The valid X pairs are: 1&9, 2&8, 3&7, 4&6. Note that 5&5 sums to 10 but standard Sudoku uniqueness rules prevent two 5s from being adjacent in most cases. The X constraint immediately limits each marked cell to a small set of candidates.
What pairs sum to 5 (V)?
The valid V pairs are: 1&4, 2&3. Only four digits can ever appear in a V cell: 1, 2, 3, or 4. This makes V markers particularly powerful for restricting candidates in the lower half of the digit range.
How does the no-symbol constraint work?
All X and V relationships are shown — if two adjacent cells have no symbol, their sum is guaranteed to be neither 5 nor 10. This negative constraint eliminates candidate pairs from unmarked cell boundaries and is often as useful as the explicit symbols.
Is XV Sudoku hard to learn?
The rules are simple to memorise. The challenge is applying both the positive (X, V) and negative (no symbol) constraints simultaneously across the entire grid. Easy puzzles are very accessible; expert puzzles require exhaustive tracking of all adjacent-cell relationships.
How long does XV Sudoku take to solve?
Easy puzzles take 8–15 minutes. Medium puzzles run 15–30 minutes. Hard puzzles average 30–60 minutes and expert puzzles often exceed 90 minutes. The no-symbol negative constraint is the most time-consuming to apply systematically across a densely marked grid.