Mathematica 9 is now available
Services & Resources / Wolfram Forums
-----
 /
MathGroup Archive
2007
*January
*February
*March
*April
*May
*June
*July
*August
*September
*October
*Archive Index
*Ask about this page
*Print this page
*Give us feedback
*Sign up for the Wolfram Insider

MathGroup Archive 2007

[Date Index] [Thread Index] [Author Index]

Search the Archive

Re: Series of LaguerreL problem

  • To: mathgroup at smc.vnet.net
  • Subject: [mg72791] Re: [mg72785] Series of LaguerreL problem
  • From: Bob Hanlon <hanlonr at cox.net>
  • Date: Sat, 20 Jan 2007 02:40:30 -0500 (EST)
  • Reply-to: hanlonr at cox.net

These are the correct first few terms of the series expansion. The complete series is

Sum[(-1)^m*FunctionExpand[LaguerreL[n-m,m,0]]*z^m/m!,
    {m,0,Infinity}]//FullSimplify

LaguerreL[n,z]


Bob Hanlon

---- Arturas Acus <acus at itpa.lt> wrote: 
> Dear Group,
> 
> 
> Using 5.2 version and looking at the help browser on LaguerreL[]
> function I see the following line
> 
> In[1]:=
> Series[LaguerreL[n, z], {z, 0, 4}]
> 
> Out[1]:=
> SeriesData[z, 0, {LaguerreL[n, 0], -LaguerreL[-1 + n, 1, 0],
> LaguerreL[-2 + n, 2, 0]/2, -LaguerreL[-3 + n, 3, 0]/6, LaguerreL[-4 + n,
> 4, 0]/24}, 0, 5, 1]
> 
> Does it have any sense? Certainly, I can call FunctionExpand[] on the
> Normal[%]
> 
> The behaviour of version 5.0 was different and I suspect bug here.
> 
> Explanation/motivation or bug confirmation would be wellcome.
> 
> 
> -- 
> Arturas Acus <acus at itpa.lt>


  • Prev by Date: Re: normalize a table
  • Next by Date: Re: normalize a table
  • Previous by thread: Series of LaguerreL problem
  • Next by thread: Re: normalize a table