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# [APL (Dyalog Unicode)], 4 bytes

 \⍨⍳9

[Try it online!][TIO]

### How it works

 ⍳9 ⍝ Integers 1..9
 ⍨ ⍝ Duplicate argument on each side
 \ ⍝ Replicate each element *n* times

### Examples

```
Index Generator: ⍳5 = 1 2 3 4 5
Expand: 2 3 \ 1 4 = 1 1 4 4 4
Commute: +⍨4 = 4 + 4 = 8
```

[APL (Dyalog Unicode)]: https://www.dyalog.com/

[TIO]: https://tio.run/##SyzI0U2pTMzJT/8PBDGPelc86t1sCQA "APL (Dyalog Unicode) – Try It Online"