Details
| Originalsprache | Englisch |
|---|---|
| Seiten (von - bis) | 119-133 |
| Seitenumfang | 15 |
| Fachzeitschrift | Discrete mathematics |
| Jahrgang | 35 |
| Ausgabenummer | 1-3 |
| Publikationsstatus | Veröffentlicht - 1981 |
Abstract
We present some combinatorial identities concerning the number T0(n,j) of all T0 topologies on n points with j open sets (which is also the number of all posets with n elements and j antichains). The average cardinality of (T0) topologies on n points is shown to be 2 n 2+O(log n).
ASJC Scopus Sachgebiete
- Mathematik (insg.)
- Theoretische Informatik
- Mathematik (insg.)
- Diskrete Mathematik und Kombinatorik
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in: Discrete mathematics, Jahrgang 35, Nr. 1-3, 1981, S. 119-133.
Publikation: Beitrag in Fachzeitschrift › Artikel › Forschung › Peer-Review
}
TY - JOUR
T1 - On the cardinalities of finite topologies and the number of antichains in partially ordered sets
AU - Erné, Marcel
PY - 1981
Y1 - 1981
N2 - We present some combinatorial identities concerning the number T0(n,j) of all T0 topologies on n points with j open sets (which is also the number of all posets with n elements and j antichains). The average cardinality of (T0) topologies on n points is shown to be 2 n 2+O(log n).
AB - We present some combinatorial identities concerning the number T0(n,j) of all T0 topologies on n points with j open sets (which is also the number of all posets with n elements and j antichains). The average cardinality of (T0) topologies on n points is shown to be 2 n 2+O(log n).
UR - http://www.scopus.com/inward/record.url?scp=0011637494&partnerID=8YFLogxK
U2 - 10.1016/0012-365X(81)90202-8
DO - 10.1016/0012-365X(81)90202-8
M3 - Article
AN - SCOPUS:0011637494
VL - 35
SP - 119
EP - 133
JO - Discrete mathematics
JF - Discrete mathematics
SN - 0012-365X
IS - 1-3
ER -