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Stripy numbers Referred to in strategy results are:

 1 2 3 4 5 6 7 8 9 9 1 2 3 4 5 6 7 8 8 9 1 2 3 4 5 6 7 7 8 9 1 2 3 4 5 6 6 7 8 9 1 2 3 4 5 5 6 7 8 9 1 2 3 4 4 5 6 7 8 9 1 2 3 3 4 5 6 7 8 9 1 2 2 3 4 5 6 7 8 9 1
 Stripy Sudoku Solver Solve Path now excludes unchecked strategies ↓
 Candidates can be Edited or Highlighted Chained Coloured,  Shown
Enter clues or solutions
 1 2 3 4 5 6 7 8 9
 Auto Tab Auto Clear
Clues+Solved: 0/81
 Pick an example here Pick an example here Only one I know

Puzzle Rules
Enter the numbers 1 to 9 uniquely in every row, column, box and each 'stripe'. Note that the stipes wrap around and all but one are in two parts.

Pick an example from the list and use [Take Step] to click through the steps of the solver so see how each puzzle solves.

 Show bi-values cells Show Strong (bi-location) links in Stripes Boxes Rows Columns 1 2 3 4 5 6 7 8 9
 A B C D E F G H J
Version 2.27
See Strategy Overview documentation

Coordinate system: Letter/Number rYcX

 1 2 3 4 5 6 7 8 9
 Check for Solved Cells Show Possibles 1: Singles 2: Naked Pairs/Triples 3: Hidden Pairs/Triples 4: Quads 5: Pointing Pairs 6: Box/Line Reduction Tough Strategies 7: X-Wing 8: Simple Colouring 9: Y-Wing 10: Rectangle Elimination 11: Swordfish 12: XYZ Wing Diabolical Strategies 13: X-Cycles 14: XY-Chain 15: 3D Medusa 16: Jellyfish 17: WXYZ Wing Extreme Strategies 19: Grouped X-Cycles 20: Finned X-Wing 21: Finned Swordfish 22: Altern. Inference Chains 23: Sue-de-Coq 24: Digit Forcing Chains 25: Nishio Forcing Chains 26: Cell Forcing Chains 27: Unit Forcing Chains 28: Almost Locked Sets 29: Death Blossom 30: Pattern Overlay Method 31: Quad Forcing Chains "Trial and Error" 32: Bowman's Bingo

Note: All Chaining strategies now permit cycling alternatives, where found read more

## The Stripy Sudoku Solver

This solver is tentative while I figure out how to make this variant. For some reason I can't fathom yet the usual code to fill a board prior to making a puzzle simple won't fill. I'm hoping it's a simple code issue but will be interesting if it is a special property of the puzzle. So only one example I can give. But you can try subtracting clues to make a harder puzzle. Take the grade with a pinch of salt.

Stripy is the same puzzle as normal Sudoku but with an extra constraint. In a similar way to the rows, columns an boxes, the stripes must also be uniquely 1 to 9. All Sudoku strategies continue to apply - except the ones that rely on the deadly pattern used by Uniqueness strategies.

All feedback, comments, arguments, bug reports and strategy ideas are welcome. There is a new FEEDBACK form with a column displaying comments and questions. Many thanks to all the people who have done so and helped improve this solver.

Version 2.19 (June 12th 2024)

Full version history here

## Solver help

Use the "Import a Sudoku" button or type in a Sudoku puzzle in the small board.
You can also pick examples from the list above. Click on Take Step to step through the solution. Unknown squares are filled with 'candidates' - possible solutions.
Any cells that are reduced to one possible candidate are solved.

You can use the [<<] button to step back one go. Toggling between Take Step and [<<] helps you see the changes.

Pressing "Enter" on the keyboard after clicking on Take Step is a quick way to activate "Take Step". Details of any solutions will be written out in the text box below the big board. Strategies are ordered by complexity. Any strategy that is successful returns the step-through to the start.

Click on the board to highlight sets of numbers. You can edit the Sudoku at any time - entering solutions in the small board or editing candidates. (Toggle between highlighting and editing using the radio buttons at the top.)

 All Solutions to a Stripy Sudoku By Andrew Stuart and Rui GonÃ§alves, Syndicated Puzzles
 Email your puzzle to a friend Copy and paste the contents of the green box into your email program and send it off. The links contain the puzzle which will load when your friend visits the Sudoku Solver.
Solver created on 11-Nov-2015.