#18784: Tutte connectors for matroids
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   Reporter:  Rudi            |            Owner:
       Type:  enhancement     |           Status:  new
   Priority:  major           |        Milestone:  sage-6.8
  Component:  matroid theory  |         Keywords:
  Merged in:                  |          Authors:
  Reviewers:                  |  Report Upstream:  N/A
Work issues:                  |           Branch:
     Commit:                  |     Dependencies:
   Stopgaps:                  |
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 Tutte's linking theorem states that if   `S`, `T` are disjoint subsets of
 the ground set of a matroid `M`, then
  `\min\{\lambda_M(X): S\subseteq X, X\cap T =\emptyset\}`
 equals
  `\max\{\lambda_N(S): E(N)=S\cup T, N= M\setminus I/ J\}`
 Here `\lambda_M(X):=r_M(X)+r_M(E-X)-r_M(E)` is the connectivity of `X` in
 `M`.

 Write a function that  outputs both an optimal `X` (a  min separation) and
 an optimal `I` (a max connector) as in Tutte's linking theorem.

--
Ticket URL: <http://trac.sagemath.org/ticket/18784>
Sage <http://www.sagemath.org>
Sage: Creating a Viable Open Source Alternative to Magma, Maple, Mathematica, 
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