arXiv 0810.13442008-10-08math.CO

Enumeration of bilaterally symmetric 3-noncrossing partitions

Guoce Xin, Terence Y. J. Zhang

备注：: 22 pages
DOI：: 10.1016/j.disc.2008.06.007

英文摘要：

Schutzenberger's theorem for the ordinary RSK correspondence naturally extends to Chen et. al's correspondence for matchings and partitions. Thus the counting of bilaterally symmetric $k$-noncrossing partitions naturally arises as an analogue for involutions. In obtaining the analogous result for 3-noncrossing partitions, we use a different technique to develop a Maple package for 2-dimensional vacillating lattice walk enumeration problems. The package also applies to the hesitating case. As applications, we find several interesting relations for some special bilaterally symmetric partitions.

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