1 | initial version |

The number `(11 - 1) / 2`

is a rational number not an integer

```
sage: parent(5)
Integer Ring
sage: parent((11 - 1) / 2)
Rational Field
```

As these objects are of different nature, the operation `is_prime`

behave differently on each of them. You should consider using one of the two workaround

```
sage: is_prime( (11 - 1) // 2) # floor division returns integer
True
sage: is_prime( Integer( (11 - 1) / 2 ) ) # conversion Rational -> Integer
True
```

2 | No.2 Revision |

The number `(11 - 1) / 2`

is a rational number not an integer

```
sage: parent(5)
Integer Ring
sage: parent((11 - 1) / 2)
Rational Field
```

As these objects are of different nature, the operation `is_prime`

~~behave ~~behaves differently on each of them. You should consider using one of the two ~~workaround~~workarounds

```
sage: is_prime( (11 - 1) // 2) # floor division returns integer
True
sage: is_prime( Integer( (11 - 1) / 2 ) ) # conversion Rational -> Integer
True
```

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