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Re: is it a bug?!please help.

• To: mathgroup at smc.vnet.net
• Subject: [mg107244] Re: [mg107199] is it a bug?!please help.
• From: Patrick Scheibe <pscheibe at trm.uni-leipzig.de>
• Date: Sat, 6 Feb 2010 03:26:15 -0500 (EST)
• References: <201002050823.DAA06688@smc.vnet.net>

Hi,

> why mathematica cannot give as output Sum[k[i],{i,1,m]]?!

because this would be wrong! 

eq = Sum[f[i], {i, 1, n}] + Sum[f[i], {i, n + 1, m}] == 
  Sum[f[i], {i, 1, m}]
eq /. {n -> 5, m -> 4}

gives

f[1] + f[2] + f[3] + f[4] + f[5] == f[1] + f[2] + f[3] + f[4]

Cheers
Patrick


On Fri, 2010-02-05 at 03:23 -0500, olfa wrote:
> Hello mathematica community,
> for Sum[k[i], {i, 1, n}] + Sum[k[i], {i, n + 1, m}]
> why mathematica cannot give as output Sum[k[i],{i,1,m]]?!
> please help.
> 

• References:
  • is it a bug?!please help.
    • From: olfa <olfa.mraihi@yahoo.fr>