MathGroup Archive 2007

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

Search the Archive

Re: binomial sum bug

  • To: mathgroup at smc.vnet.net
  • Subject: [mg82637] Re: binomial sum bug
  • From: Bill Rowe <readnewsciv at sbcglobal.net>
  • Date: Fri, 26 Oct 2007 05:33:13 -0400 (EDT)

On 10/25/07 at 6:06 AM, jack at realmode.com (Jack Kennedy) wrote:

>In:  Sum[Binomial[5,2k],{k,0,5}]
>Out: 16

>In:  Sum[Binomial[n,2k],{k,0,n}] /. n->5
>Out:  -16

>What the?

>This has been addressed before [mg70486] about a year ago and a work
>around was posted but I have two questions:
>
>1. Was it declared a bug by Wolfrram, and 2. In general does
>Wolfram issue bug fixes, and specifically is there a
>patch for this problem?

>$Version = 5.1 for Microsoft Windows (October 25, 2004)

Given:

In[1]:= Sum[Binomial[5, 2 k], {k, 0, 5}]

Out[1]= 16

In[2]:= Sum[Binomial[n, 2 k], {k, 0, n}] /. n -> 5

Out[2]= 16

In[3]:= $Version

Out[3]= 6.0 for Mac OS X PowerPC (32-bit) (June 19, 2007)

It is clear it was a bug that has been corrected.
--
To reply via email subtract one hundred and four


  • Prev by Date: Re: Selecting Rows Where All Columns Satisfy a Condition
  • Next by Date: Re: Selecting Rows Where All Columns Satisfy a Condition
  • Previous by thread: Re: binomial sum bug
  • Next by thread: Re: binomial sum bug