### What is a PARI group?

Take for instance the example:

```
G = NumberField(x^5 + 15*x + 12, 't').galois_group(type="pari"); G
```

This gives an output:

```
Galois group PARI group [20, -1, 3, "F(5) = 5:4"] of degree 5 of the Number Field in t with defining polynomial x^5 + 15*x + 12
```

So I wonder what is the meaning of [20, -1, 3, "F(5) = 5:4"]. Is it some kind of permutation?

The relevant page of the documentation doesn't clarify it.