LLMs have already told you these are "known solutions", which implicitly means they are established, non-original approaches. So the key point is really on the user side—if you simply ask one more question, like where these "known solutions" come from, the LLM will likely tell you that these formulas are attributed to Inigo Quilez.

So in my view, if you treat an LLM as a tool for retrieving knowledge or solutions, there isn't really a problem here. And honestly, the line between "knowledge" and "creation" can be quite blurry. For example, when you use Newton's Second Law (F = ma), you don't explicitly state that it comes from Isaac Newton every time—but that doesn't mean you're not respecting his contribution.