[Fwd: Re: [PURRS-devel] base case assumptions]

[Roberto Bagnara]

-------- Original Message --------
Subject: Re: [PURRS-devel] base case assumptions
Date: Mon, 29 Dec 2003 21:22:03 -0500
From: Shailesh Humbad <humbads at alum.mit.edu>
To: Roberto Bagnara <bagnara at cs.unipr.it>
References: <6.0.0.22.0.20031226022754.01ccf318 at nyip.net> 
<3FEF09D2.2040706 at cs.unipr.it>

Thanks for confirming my suspicion and for making the research demo 
available online.  It's a very useful tool for those of us who don't 
have access to Mathematica.

By the way, when the base cases are defined and a correction term added 
to the formula given by PURRS, the solution to the recurrence reduces to 
[(n-2)*(n-1)]/2.

Regards,
Shailesh

At 11:50 AM 12/28/2003, you wrote:
>Shailesh Humbad wrote:
>>I am having a problem with the online version of PURRS.
>> I tried it on a recurrence relation derived from an algorithm
>> I'm working on, and the resulting formula is off by one for even n.
>> I believe it may be something to do with our assumptions for the base
>> cases and starting index.  Is that something that would affect the results?
>
>Dear Shailesh,
>
>you are right: the online demo assumes that, for a recurrence of order
>k, the initial conditions are given for x(0), ..., x(k-1).
>We are working at a revision of our system (that currently is, remember,
>only a research prototype) that will allow to specify any set of
>initial conditions and special cases.
>We will also extend the online demo so as to make this facilities
>available through the web.
>
>>Thanks and Happy Holidays,
>
>Thanks for your input.
>Have a great 2004,
>
>    Roberto Bagnara on behalf of the PURRS team
>
>-- 
>Prof. Roberto Bagnara
>Computer Science Group
>Department of Mathematics, University of Parma, Italy
>http://www.cs.unipr.it/~bagnara/
>mailto:bagnara at cs.unipr.it


-- 
Prof. Roberto Bagnara
Computer Science Group
Department of Mathematics, University of Parma, Italy
http://www.cs.unipr.it/~bagnara/
mailto:bagnara at cs.unipr.it