On the Möbius function and topology of general pattern posets
The electronic journal of combinatorics, Tome 26 (2019) no. 1
We introduce a formal definition of a pattern poset which encompasses several previously studied posets in the literature. Using this definition we present some general results on the Möbius function and topology of such pattern posets. We prove our results using a poset fibration based on the embeddings of the poset, where embeddings are representations of occurrences. We show that the Möbius function of these posets is intrinsically linked to the number of embeddings, and in particular to so called normal embeddings. We present results on when topological properties such as Cohen-Macaulayness and shellability are preserved by this fibration. Furthermore, we apply these results to some pattern posets and derive alternative proofs of existing results, such as Björner's results on subword order.
@article{10_37236_7919,
author = {Jason P. Smith},
title = {On the {M\"obius} function and topology of general pattern posets},
journal = {The electronic journal of combinatorics},
year = {2019},
volume = {26},
number = {1},
doi = {10.37236/7919},
zbl = {1516.06005},
url = {http://geodesic.mathdoc.fr/articles/10.37236/7919/}
}
Jason P. Smith. On the Möbius function and topology of general pattern posets. The electronic journal of combinatorics, Tome 26 (2019) no. 1. doi: 10.37236/7919
Cité par Sources :