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DEGREE OF THE $W$-OPERATOR AND NONCROSSING PARTITIONS

Published online by Cambridge University Press:  23 October 2019

HAO SUN*
Affiliation:
Department of Mathematics, Sun Yat-Sen University, 135 Xingang W Rd, BinJiang Lu, Haizhu Qu, Guangzhou Shi, Guangdong Sheng, China email [email protected]

Abstract

The $W$-operator, $W([n])$, generalises the cut-and-join operator. We prove that $W([n])$ can be written as the sum of $n!$ terms, each term corresponding uniquely to a permutation in $S_{\!n}$. We also prove that there is a correspondence between the terms of $W([n])$ with maximal degree and noncrossing partitions.

Type
Research Article
Copyright
© 2019 Australian Mathematical Publishing Association Inc.

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