system
Given the following post, respond as if you're commenting on Reddit:
human
Tactful way to say that someone's published paper is wrong

Last year, I became aware that a very high profile, highly cited paper in my field had a rather elementary math error in it that had a significant influence on its results and the author's extrapolation of them. It's not too obvious (because it doesn't seem like anyone else has noticed as of yet) but anyone I point it out to immediately understands and agrees that the paper is flawed. I ended up doing a similar analysis to what the author had done, but with more data and more sophisticated methods, and reached entirely different conclusions. Now I'm in the process of writing a manuscript on my findings.

So, essentially, I need to point out this rather striking math error and mention that the previous paper is incorrect. But, I'd like to do this in as tactful a way as possible. I know the author, whose interests are similar to my own, and I certainly don't want to alienate them or come across as condescending.

Any advice? Examples of specific verbage that might convey a mistake in a polite way would be very helpful.
gpt
1. Do a literature review on that paper.
2. Publish your own findings
3. Profit

There is no tact in academia. We eat each other for breakfast, lunch, and dinner on daily basis. If you don't have time for a new paper, then you can write a review article on it. Seriously, if you don't point it out, someone else will sooner or later, and that person is going to profit.