Petersen T. Eulerian Numbers 2015 torrent

Textbook in PDF format

Offers a self-contained treatment of progress and problems related to the Eulerian numbers
Covers a topic that plays an important role in combinatorics, number theory, and topology
Provides previously-unpublished coverage of gamma-nonnegativity of a simplicial complex and its results in combinatorial terms
Includes discussion of open problems and directions for future research, as well as numerous exercises and examples
This text presents the Eulerian numbers in the context of modern enumerative, algebraic, and geometric combinatorics. The book first studies Eulerian numbers from a purely combinatorial point of view, then embarks on a tour of how these numbers arise in the study of hyperplane arrangements, polytopes, and simplicial complexes. Some topics include a thorough discussion of gamma-nonnegativity and real-rootedness for Eulerian polynomials, as well as the weak order and the shard intersection order of the symmetric group.
The book also includes a parallel story of Catalan combinatorics, wherein the Eulerian numbers are replaced with Narayana numbers. Again there is a progression from combinatorics to geometry, including discussion of the associahedron and the lattice of noncrossing partitions.
The final chapters discuss how both the Eulerian and Narayana numbers have analogues in any finite Coxeter group, with many of the same enumerative and geometric properties. There are four supplemental chapters throughout, which survey more advanced topics, including some open problems in combinatorial topology.
This textbook will serve a resource for experts in the field as well as for graduate students and others hoping to learn about these topics for the first time.​
About the Author. T. Kyle Petersen is an Associate Professor of Mathematics at DePaul University, Chicago, USA. His research areas include algebraic, enumerative, and topological combinatorics. He received his PhD in Mathematics from Brandeis University.
Topics
Combinatorics
Topology
Number Theory
Group Theory and Generalizations
Discrete Mathematics