====== Steven Tedford (Franklin and Marshall) ======

====== Connectivity in Lifts of Greedoids ======

===== Abstract for the Combinatorics Seminar 2006 April 27 =====

A //greedoid// is an abstract combinatorial structure that captures the essence of the greedy algorithm in combinatorial optimization.

From a given greedoid one can form new ones by a construction called //lifting//. Theorem: When a greedoid is k-connected, then all of its lifts are, too.

I will introduce greedoids and required background that leads to this result. I will also discuss sufficient and necessary conditions for the lift of an undirected branching greedoid to be two-connected.


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