> For the complete documentation index, see [llms.txt](https://trizen.gitbook.io/sidef-lang/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://trizen.gitbook.io/sidef-lang/programming_tasks/s/square_but_not_cube.md).

# Square but not cube

```ruby
var square_and_cube = Enumerator({|f|
    1..Inf -> each {|n| f(n**6) }
})

var square_but_not_cube = Enumerator({|f|
    1..Inf -> lazy.map {|n| n**2 }.grep {|n| !n.is_power(3) }.each {|n| f(n) }
})

say "First 30 positive integers that are a square but not a cube:"
say square_but_not_cube.first(30).join(' ')

say "First 15 positive integers that are both a square and a cube:"
say square_and_cube.first(15).join(' ')
```

## Output:

```
First 30 positive integers that are a square but not a cube:
4 9 16 25 36 49 81 100 121 144 169 196 225 256 289 324 361 400 441 484 529 576 625 676 784 841 900 961 1024 1089
First 15 positive integers that are both a square and a cube:
1 64 729 4096 15625 46656 117649 262144 531441 1000000 1771561 2985984 4826809 7529536 11390625
```


---

# Agent Instructions
This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com.

## Querying This Documentation
If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter, and the optional `goal` query parameter:

```
GET https://trizen.gitbook.io/sidef-lang/programming_tasks/s/square_but_not_cube.md?ask=<question>&goal=<endgoal>
```

`ask` is the immediate question: it should be specific, self-contained, and written in natural language.
`goal` is optional and describes the broader end goal you are ultimately trying to accomplish on behalf of the user. GitBook uses it to tailor the answer towards what is most useful for that goal.

The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.