LegendreP of order = -1

*To*: mathgroup at smc.vnet.net*Subject*: [mg58936] LegendreP of order = -1*From*: "symbio" <symbio at has.com>*Date*: Sun, 24 Jul 2005 01:21:55 -0400 (EDT)*Reply-to*: "symbio" <symbio at sha.com>*Sender*: owner-wri-mathgroup at wolfram.com

Hi, I'm trying to solve an electrodynamics problem in spherical coordinates and need to use Legendre Polynomials. Can anyone tell me what is the correct mathematical value for LegendreP[-1,1] supposed to be? Is it +1 or -1, and more importantly WHY? I have a math book here which says it should be -1, but Mathematica gives +1, so which is correct? So the question is: LegendrePolynomial[n = -1, x = 1] = ???

**Follow-Ups**:**Re: LegendreP of order = -1***From:*Curtis Osterhoudt <gardyloo@mail.wsu.edu>