A computer-oriented method for the enumeration and generation of physical trees is presented. Physical trees depict acyclic chemical structures, but the term physical is used to stress the process by which the structures are produced.
Enumeration of trees by inversions
β Scribed by Ira M. Gessel; Bruce E. Sagan; Yeong-Nan Yeh
- Publisher
- John Wiley and Sons
- Year
- 1995
- Tongue
- English
- Weight
- 749 KB
- Volume
- 19
- Category
- Article
- ISSN
- 0364-9024
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β¦ Synopsis
Abstract
Mallows and Riordan βThe Inversion Enumerator for Labeled Trees,β Bulletin of the American Mathematics Society, vol. 74 [1968] pp. 92β94) first defined the inversion polynomial, J~n~(q) for trees with n vertices and found its generating function. In the present work, we define inversion polynomials for ordered, plane, and cyclic trees, and find their values at q = 0, Β± 1. Our techniques involve the use of generating functions (including Lagrange inversion), hypergeometric series, and binomial coefficient identities, induction, and bijections. We also derive asymptotic formulae for those results for which we do not have a closed form. Β© 1995 John Wiley & Sons, Inc.
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