1 | initial version |

Some hints:

Look at the parent of X, and a:

```
sage: X.parent()
sage: a.parent()
sage: a.parent() == R
```

In your example, replace

```
sage: X = polygen(R)
```

by

```
sage: X = R.gen()
```

And redo everything.

Compare the documentations of both:

```
sage: X = polygen?
sage: R.gen?
```

2 | No.2 Revision |

Some hints:

Look at the parent of X, and a:

```
sage: X.parent()
sage: a.parent()
sage: a.parent() == R
```

In your example, replace

```
sage: X = polygen(R)
```

by

```
sage: X = R.gen()
```

And redo everything.

Compare the documentations of both:

```
sage: X = polygen?
sage: R.gen?
```

Ask if you need more details.

3 | No.3 Revision |

Some hints:

Look at the documentation of `polygen`

:

```
sage: X = polygen?
```

Look at the parent of ~~X, and a:~~`X`

(and `a`

):

```
sage: X.parent()
sage: a.parent()
sage: a.parent() == R
sage: X.base_ring()
```

In your example, replace

```
sage: X = polygen(R)
```

by

```
sage: X = R.gen()
```

And redo ~~everything.~~

Compare the documentations of both:

ever test to understand where your previous

~~sage: X = polygen? sage: R.gen?~~X

Ask was living and why. Do not hesitate to ask if you need more details.

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