To build on this, factoids in general are not copyrightable. This was the linchpin of a pretty famous lawsuit that a writer of a popular trivia book, Fred Worth, brought against Trivial Pursuit since many of the questions from the first edition were directly derived from factoids in his book "The Trivia Encyclopedia".<p><a href="https://en.wikipedia.org/wiki/The_Trivia_Encyclopedia" rel="nofollow">https://en.wikipedia.org/wiki/The_Trivia_Encyclopedia</a>
For the avoidance of doubt it’s also better if you “clean room reverse” things that are common knowledge because in the process of doing so you can make a bunch of superior posts about how you are uniquely the only person smart enough to do it this way. It makes you look really cool to nerds on the internet and as a bonus parallel construction is a lot easier to do.