Re: Limit of an Integer Function

*To*: mathgroup at smc.vnet.net*Subject*: [mg18839] Re: [mg18767] Limit of an Integer Function*From*: BobHanlon at aol.com*Date*: Thu, 22 Jul 1999 22:57:42 -0400*Sender*: owner-wri-mathgroup at wolfram.com

Phil, For the example given, you do not need the limit, you need Mathematica to make use of the fact that n is an integer. In version 4, Simplify with the conditional that n is an element of the integers: Simplify[Sin[n Pi], Element[n, Integers]] 0 Bob Hanlon In a message dated 7/20/99 8:12:40 AM, mend0070 at tc.umn.edu writes: >I seem to have found a blind spot in my knowledge of how to get >Mathematica to evaluate limits. > >I want to evaluate the limit of a function where the domain is a member >of the Natural numbers, such as infinite series. It seems that Limit >assumes that the function is continuous. > >For example, if I asked > >Limit[Sin[ n Pi ],n-> Infinity], mathematica would return: >Interval[{-1,1}]. This is true if n is a member of the Reals, but not >true if n is a positive integer (in which case the limit would be 0.] > >Is there another function I should use? Or would it be nice to specify >the domain of the function as a feature request? >