#14846: CycleIndexSeries derivative, integral, exponential methods are not
combinatorial
-------------------------------------+-------------------------------------
       Reporter:  agd                |        Owner:  agd
           Type:  enhancement        |       Status:  positive_review
       Priority:  major              |    Milestone:  sage-6.8
      Component:  combinatorics      |   Resolution:
       Keywords:  LazyPowerSeries,   |    Merged in:
  species                            |    Reviewers:  Martin Rubey
        Authors:  Andrew Gainer-     |  Work issues:  documentation
  Dewar                              |       Commit:
Report Upstream:  N/A                |  ab9c7d161b8318bc5edffb3bb3dd66bc5c503318
         Branch:  u/agd/cis/deriv    |     Stopgaps:
   Dependencies:                     |
-------------------------------------+-------------------------------------
Changes (by mantepse):

 * status:  needs_review => positive_review


Comment:

 I played with the code and the examples, and found myself happy.  For
 example,

 {{{
 sage: T = CombinatorialSpecies()
 sage: X = species.SingletonSpecies()
 sage: E = species.SetSpecies()
 sage: T.define(X*E(T))
 sage: s = T.cycle_index_series()
 sage: oeis(s.logarithm().generating_series().counts(12))
 0: A133297: a(n) = n!*Sum_{k=1..n} (-1)^(k+1)*n^(n-k-1)/(n-k)!.
 sage: oeis(s.pointing().generating_series().counts(12)[1:])
 0: A000312: Number of labeled mappings from n points to themselves
 (endofunctions): n^n.
 1: A177885: (1-n)^(n-1).
 2: A086783: Discriminant of the polynomial x^n - 1.
 sage: oeis(s.pointing().isotype_generating_series().counts(12)[1:])
 0: A000107: Number of rooted trees with n nodes and a single labeled node;
 pointed rooted trees; vertebrates.
 }}}

 Thanks for the code and thanks for the patience!

--
Ticket URL: <http://trac.sagemath.org/ticket/14846#comment:37>
Sage <http://www.sagemath.org>
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