Parity Cells
Values in the marked cells have the stated parity: odd or even.
Parameters
| Parameter | Meaning | Default |
|---|---|---|
| parity | The required parity: odd or even. | Required. |
| cells | The marked cells, for example r1c1-r1c2-r2c2. | Required. |
Maths
Class: first-order.
The shared predicates define the notation and every named predicate.
∀c∈cells: ⌊V(c)⌋=V(c) ∧ (parity="odd" → odd(V(c))) ∧ (parity="even" → rem(V(c),2)=0)
Every V value has parity named by parity: odd has absolute remainder 1, even remainder 0 modulo 2.
Example
---
format: open-rules
title: Parity Cells example
setter: Example
source: ""
case: ""
library: https://rules.sudoku-sleuth.com/
status: read
---
```rules
sudoku 9x9
parity-cells r1c1-r1c2 parity "odd"
```
Satisfies the rule: r1c1=1, r1c2=3. Both marked digits are odd.
Breaks the rule: r1c1=1, r1c2=2. A marked cell contains the even digit 2.