I don't know how you'd prompt this, but if there was a clean example of an A.I. coming up with an idea that's completely novel in more than details, it would be compelling evidence that these next-token predictors have some weird emergent properties that don't necessarily follow from intricate, sophisticated webs of token-prediction.

E.g. "What might be a room-temperature superconductor" -> "some plausible iteration on existing high-temperature superconductors based on our current understanding of the underlying physics" would not be outside how we currently understand them.

"What might be a room-temperature superconductor?" -> "some completely outlandish material that nobody has studied before and, when examined, seems to have higher temperature superconducting than we would predict" would provoke some serious questions.

A fun experiment I've heard suggested is training a model on all scientific understanding just up to some counterintuitive quantum leap in scientific understanding, say, Einstein's theory of relativity, and then seeing if you can prompt it to "discover" or "invent" said leap, without explicitly telling it what to look for. This would of course be pretty hard to prove, but if you could get it to work on a local model, publish the training set and parameters so that anyone can replicate it on their own machine, that could be pretty darn compelling.

Programs are fundamentally lists of instructions. LLMs are very good at building these lists. That it performs well when you say "Build a list you've seen before, but do it in a slightly different way this time. Here's the exact way I want you to do it." is not surprising. I would honestly be surprised if it couldn't do it.

As the other commenter suggested, a genuinely novel scientific idea would be surprising. A new style of art (think Picasso or Pollack coming along), not just an iteration on Ghibli, would be surprising. That's actual creativity.