| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 420550 | Discrete Applied Mathematics | 2009 | 6 Pages |
Abstract
Several important combinatorial arrays, after inserting some minus signs, turn out to be involutions when considered as lower triangular matrices. Among these are the Pascal, RNA, and directed animal matrices. These examples and many others are in the Bell subgroup of the Riordan group. We characterize all such pseudo-involutions by means of a single sequence called the ΔΔ-sequence. Finally we compute the ΔΔ-sequences for the powers of a pseudo-involution in the Bell subgroup.
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Physical Sciences and Engineering
Computer Science
Computational Theory and Mathematics
Authors
Gi-Sang Cheon, Sung-Tae Jin, Hana Kim, Louis W. Shapiro,