factorization of symmetric functions

[mantepse]

We implement factor, gcd and _floordiv_ for symmetric functions, and thus make them a UniqueFactorizationDomain.

CC: @tscrim

Component: combinatorics

Author: Martin Rubey

Branch/Commit: 6e1f451

Reviewer: Travis Scrimshaw

Issue created by migration from https://trac.sagemath.org/ticket/34515

[7ed8c4ca-6d56-4ae9-953a-41e42b4ed313]

Changed commit from a52bc66 to 114189a

[7ed8c4ca-6d56-4ae9-953a-41e42b4ed313]

Branch pushed to git repo; I updated commit sha1. New commits:

114189a

Merge branch 'develop' of trac.sagemath.org:sage into t/34515/factorization_of_symmetric_functions

[7ed8c4ca-6d56-4ae9-953a-41e42b4ed313]

Changed commit from 114189a to f4542dd

[7ed8c4ca-6d56-4ae9-953a-41e42b4ed313]

Branch pushed to git repo; I updated commit sha1. New commits:

d95f9ba	Merge branch 'u/tscrim/categories_lazy_series-34470' of https://github.com/sagemath/sagetrac-mirror into u/tscrim/parent_plethysm-27652
9280ad9	make plethysm with tensor return result as element of second parent
5b8a696	Merge branch 'u/mantepse/parent_of_plethysm' of https://github.com/sagemath/sagetrac-mirror into u/tscrim/parent_plethysm-27652
c501119	Making the result not depend on the input.
bad6489	Adding some doctests and documentation on the plethysm output.
0dcc0aa	Merge branch 'develop' of trac.sagemath.org:sage into t/27652/parent_plethysm-27652
f4542dd	Merge branch 'u/mantepse/parent_plethysm-27652' of trac.sagemath.org:sage into t/34515/factorization_of_symmetric_functions

[7ed8c4ca-6d56-4ae9-953a-41e42b4ed313]

Changed commit from f4542dd to 6e1f451

[7ed8c4ca-6d56-4ae9-953a-41e42b4ed313]

Branch pushed to git repo; I updated commit sha1. New commits:

6e1f451

remove unused import

[vbraun]

Changed branch from u/mantepse/factorization_of_symmetric_functions to 6e1f451