DOAJ
Open Access
2011
Counting self-dual interval orders
Vít Jelínek
Abstrak
In this paper, we first derive an explicit formula for the generating function that counts unlabeled interval orders (a.k.a. (2+2)-free posets) with respect to several natural statistics, including their size, magnitude, and the number of minimal and maximal elements. In the second part of the paper, we derive a generating function for the number of self-dual unlabeled interval orders, with respect to the same statistics. Our method is based on a bijective correspondence between interval orders and upper-triangular matrices in which each row and column has a positive entry.
Topik & Kata Kunci
Penulis (1)
V
Vít Jelínek
Akses Cepat
Informasi Jurnal
- Tahun Terbit
- 2011
- Sumber Database
- DOAJ
- DOI
- 10.46298/dmtcs.2932
- Akses
- Open Access ✓