# More Groupokus
([home](https://github.com/alexhkurz/introduction-to-numbers/blob/master/README.md) ... [previous](https://hackmd.io/@alexhkurz/B1w9oSPiL) ... [next](https://hackmd.io/@alexhkurz/S17OoT2oI))
Recall the rules of [Groupoku](https://hackmd.io/@alexhkurz/B1w9oSPiL):
- Every row and column needs to contain every number exactly once (unique solution to equations $ax=b$).
- The top-left down-right diagonal gives a mirror symmetry (commutativity).
- At the end we need to check for associativity using the program [groupoku](https://github.com/alexhkurz/introduction-to-numbers/blob/master/src/groupoku.py).
**Groupoku:** Show that there is one and only one solution to
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**Groupoku:** Show that there is exactly one solution to
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|:---:|:---:|:---:|:---:|:---:|
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**Groupoku:** Show that there is exactly one solution to
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|:---:|:---:|:---:|:---:|:---:|
| 1 |0||
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**Groupoku:** Show that there is exactly one solution to
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| 1|2||
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**Groupoku:** Show that there is exactly one solution to
|0| 1| 2| 3|4
|:---:|:---:|:---:|:---:|:---:|
| 1|2||
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**Groupoku:** Show that there is exactly one solution to
|0| 1| 2| 3|4
|:---:|:---:|:---:|:---:|:---:|
| 1|3||
| 2||1||
| 3||||
| 4||||
**Groupoku:** Show that there is exactly one solution to
|0| 1| 2| 3|4
|:---:|:---:|:---:|:---:|:---:|
| 1|3||
| 2||4||
| 3||||
| 4||||
**Groupoku:** Show that there is exactly one solution to
|0| 1| 2| 3|4
|:---:|:---:|:---:|:---:|:---:|
| 1|4||
| 2||1||
| 3||||
| 4||||
**Groupoku:** Show that there is exactly one solution to
|0| 1| 2| 3|4
|:---:|:---:|:---:|:---:|:---:|
| 1|4||
| 2||3||
| 3||||
| 4||||