There is a mathematical concept in wikipedia. Its a ranking function. Can be found here. The fact that the knowledge is out there makes me think I can use it in my software.
However, when I do a patent search for this term I come up with many hits. I haven't gone through those documents in details, but now I am thinking I can't really use that technique in my software. The particular technique has many variations. And in one of the patent document I've read the claims that say, it is claiming not only the technique, but variations of the mathematical technique.
So does this actually mean I cannot use it?