Applied Algebra Seminar

York University - Fall 2002

December 12, 2002 - 2:00pm
Fields Institute - Stewart Library

Speaker: Mikhail Kogan (Northeastern University)



Rc-graphs and Schensted insertion algorithm



Schensted insertion algorithm for Young tableaux provides a combinatorial rule for computing Littlewood-Richardson coefficients (structure constants of grassmannians). We discuss modifications of this algorithm which work with rc-graphs instead of Young tableaux and provide rules for computing generalized Littlewood-Richardson coefficients (structure constants of flag manifolds). The latest version of the algorithm computes the coefficients $c^u_{wv}$ in the cases when v is a grassmannian permutation, whose shape is a hook, or in the case when v is a grassmannian permutation with the single descent at $k$ and w is a permutation with no descents greater than $k$. The algorithm also allows to generalize the RSK correspondence in these cases.



Algebra Seminar Home - Fall 2002