error with Sum and Infinity

*To*: mathgroup at smc.vnet.net*Subject*: [mg102245] error with Sum and Infinity*From*: Llewlyn <tommaso.biancalani at gmail.com>*Date*: Sun, 2 Aug 2009 06:01:39 -0400 (EDT)

Hi experts, i'm very new to Mathematica and this is my first problem. I define a function that is 0 everywhere: t[i_] := 0 expect for point i =3 that is: t[3] = 1 If now i evaluate the finite sum i obtain 1 as expected Sum[ t[i], {i, 1, 10}] Out = 1 but if i try do the same with infinity i obtain In[808]:= Sum[ t[i], {i, 1, Infinity}] Out[808]= 0 instead of 1 expected. Any advice? tb

**Follow-Ups**:**Re: error with Sum and Infinity***From:*Andrzej Kozlowski <akoz@mimuw.edu.pl>

**Re: error with Sum and Infinity***From:*Tomas Garza <tgarza10@msn.com>