The centre of a Steiner loop and the maxi-Pasch problem
Commentationes Mathematicae Universitatis Carolinae, Tome 61 (2020) no. 4, pp. 535-545.

Voir la notice de l'article provenant de la source Czech Digital Mathematics Library

A binary operation ``$\cdot$'' which satisfies the identities $x\cdot e = x$, $x \cdot x = e$, $(x \cdot y) \cdot x = y$ and $x \cdot y = y \cdot x$ is called a Steiner loop. This paper revisits the proof of the necessary and sufficient conditions for the existence of a Steiner loop of order $n$ with centre of order $m$ and discusses the connection of this problem to the question of the maximum number of Pasch configurations which can occur in a Steiner triple system (STS) of a given order. An STS which attains this maximum for a given order is said to be {\it maxi-Pasch}. We show that loop factorization preserves the maxi-Pasch property and find that the Steiner loops of all currently known maxi-Pasch Steiner triple systems have centre of maximum possible order.
DOI : 10.14712/1213-7243.2020.035
Classification : 05B07, 20N05
Keywords: Steiner loop; centre; nucleus; Steiner triple system; Pasch configuration; quadrilateral
@article{10_14712_1213_7243_2020_035,
     author = {Kozlik, Andrew R.},
     title = {The centre of a {Steiner} loop and the {maxi-Pasch} problem},
     journal = {Commentationes Mathematicae Universitatis Carolinae},
     pages = {535--545},
     publisher = {mathdoc},
     volume = {61},
     number = {4},
     year = {2020},
     doi = {10.14712/1213-7243.2020.035},
     mrnumber = {4230958},
     zbl = {07332727},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.14712/1213-7243.2020.035/}
}
TY  - JOUR
AU  - Kozlik, Andrew R.
TI  - The centre of a Steiner loop and the maxi-Pasch problem
JO  - Commentationes Mathematicae Universitatis Carolinae
PY  - 2020
SP  - 535
EP  - 545
VL  - 61
IS  - 4
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/articles/10.14712/1213-7243.2020.035/
DO  - 10.14712/1213-7243.2020.035
LA  - en
ID  - 10_14712_1213_7243_2020_035
ER  - 
%0 Journal Article
%A Kozlik, Andrew R.
%T The centre of a Steiner loop and the maxi-Pasch problem
%J Commentationes Mathematicae Universitatis Carolinae
%D 2020
%P 535-545
%V 61
%N 4
%I mathdoc
%U http://geodesic.mathdoc.fr/articles/10.14712/1213-7243.2020.035/
%R 10.14712/1213-7243.2020.035
%G en
%F 10_14712_1213_7243_2020_035
Kozlik, Andrew R. The centre of a Steiner loop and the maxi-Pasch problem. Commentationes Mathematicae Universitatis Carolinae, Tome 61 (2020) no. 4, pp. 535-545. doi : 10.14712/1213-7243.2020.035. http://geodesic.mathdoc.fr/articles/10.14712/1213-7243.2020.035/

Cité par Sources :