There has been some work on recurrences, if you search the issue tracker and pull request list for "recurrence" you can find some of it. I'm not aware of any work along the lines of what you are suggesting.
Regarding the evaluation of recurrences, there has been some work in the new sympy.discrete.recurrences submodule. Making SeqBase support recursive sequences sounds like a good idea. One would need to make sure that all the methods work properly when the sequence is recursive. Aaron Meurer On Sun, Aug 26, 2018 at 1:02 PM, Robert Dougherty-Bliss <[email protected]> wrote: > I have recently been working with linear recurrence relations with constant > and / or polynomial coefficients w.r.t. the index. (These are called > C-finite and P-recursive sequences, respectively.) These sequences have some > nice properties, such as easy closed-form expressions in the C-finite case > from Binet's formula. Ultimately, I would like to do things in the vein of > Doron Zeilberger's GuessHolo package for P-recursive sequences, as described > in this paper. > > Has anyone looked into creating a subclass of SeqBase (or something more > appropriate) for recursive sequences? Perhaps specifically for C-finite and > P-recursive sequences? It seems like this would be convenient in general. > For instance, every sequence implements a method to guess a C-finite > sequence that it might be (find_linear_recurrence()), but then just returns > a list of coefficients rather than a complete sequence object. Outside of > C-finite sequences, memoization could be baked in to make the evaluation of > less-trivial recursive sequences nicer. > > -- > You received this message because you are subscribed to the Google Groups > "sympy" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > To post to this group, send email to [email protected]. > Visit this group at https://groups.google.com/group/sympy. > To view this discussion on the web visit > https://groups.google.com/d/msgid/sympy/d8c5f383-ee72-4c9a-b9a9-4c18fb91f8dd%40googlegroups.com. > For more options, visit https://groups.google.com/d/optout. -- You received this message because you are subscribed to the Google Groups "sympy" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at https://groups.google.com/group/sympy. To view this discussion on the web visit https://groups.google.com/d/msgid/sympy/CAKgW%3D6LJWEOWA%3DgRV6NqHiSoL-eqkPtvVsovJ_F%2BWGFHsfDq2A%40mail.gmail.com. For more options, visit https://groups.google.com/d/optout.
