Ralf Stephan on Sun, 15 May 2016 09:41:57 +0200


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Re: periodic generating function


? poliscyclo(1+x+x^2)
%1 = 3
? poliscyclo(1+x+x^3)
%2 = 0

This is for C=1. However for example:

? factor(1-4*x^12)
%3 =
[2*x^6 - 1 1]

[2*x^6 + 1 1]

? poliscyclo(2*x^6 + 1)
%4 = 0


On Sun, May 15, 2016 at 9:18 AM Kevin Ryde <user42_kevin@yahoo.com.au> wrote:
To notice a periodic part in a generating function I think I want to
find whether a denominator polynomial is a divisor of 1 - C*x^p, for
some constant C and some power p.  What would be a good way to do that?

I got the effect I wanted by working upwards determining successive
terms of quotient until only a high term (or stop if too long).
Coefficients might be complex or quad and I'm happy for C to be
likewise.