Enumeration of Graded (3 + 1)-Avoiding Posets
oleh: Joel Lewis Brewster, Yan X Zhang
| Format: | Article |
|---|---|
| Diterbitkan: | Discrete Mathematics & Theoretical Computer Science 2012-01-01 |
Deskripsi
The notion of (3+1)-avoidance appears in many places in enumerative combinatorics, but the natural goal of enumerating all (3+1)-avoiding posets remains open. In this paper, we enumerate \emphgraded (3+1)-avoiding posets. Our proof consists of a number of structural theorems followed by some generating function magic.