I'm in the first of 3 courses in quantum mechanics, and we just started chapter 4 of Griffiths. He goes into great detail in most of the solution of the radial equation, except for one part: translating the recursion relation into a form that matches the definition of the Laguerre polynomials. Now I understand the technique that gets all the way to that point, but I have yet to find any derivation that actually shows how that recursion relation is made to match the right form. I spent a while on it but I can't get it quite right. Can anyone show, or point me to a derivation that includes this detail? Thanks.