## Zhang, Yan X - Four Variations on Graded Posets

dmtcs:2492 - Discrete Mathematics & Theoretical Computer Science, January 1, 2015, DMTCS Proceedings, 27th International Conference on Formal Power Series and Algebraic Combinatorics (FPSAC 2015)

Authors: Zhang, Yan X

We explore the enumeration of some natural classes of graded posets, including $(2 + 2)$-avoiding graded posets, $(3 + 1)$-avoiding graded posets, $(2 + 2)$- and $(3 + 1)$-avoiding graded posets, and the set of all graded posets. As part of this story, we discuss a situation when we can switch between enumeration of labeled and unlabeled objects with ease, which helps us generalize a result by Postnikov and Stanley from the theory of hyperplane arrangements, answer a question posed by Stanley, and see an old result of Klarner in a new light.

Source : oai:HAL:hal-01337770v1
Volume: DMTCS Proceedings, 27th International Conference on Formal Power Series and Algebraic Combinatorics (FPSAC 2015)
Section: Proceedings
Published on: January 1, 2015
Submitted on: November 21, 2016
Keywords: posets,combinatorics,generating functions,poset avoidance,linear algebra,[INFO.INFO-DM] Computer Science [cs]/Discrete Mathematics [cs.DM]