Just a remark: for all your elementary needs regarding special functions, the one-stop shop is the [Digital Library of Mathematical Functions][1]. 

There is an [index][2], and you find what you are looking for [here][3].


  [1]: https://dlmf.nist.gov/
  [2]: https://dlmf.nist.gov/idx/
  [3]: https://dlmf.nist.gov/6.2#i