×

Coherent configurations associated with TI-subgroups. (English) Zbl 1387.05271

Summary: Let \(\mathcal{X}\) be a coherent configuration associated with a transitive group \(G\). In terms of the intersection numbers of \(\mathcal{X}\), a necessary condition for the point stabilizer of \(G\) to be a TI-subgroup, is established. Furthermore, under this condition, \(\mathcal{X}\) is determined up to isomorphism by the intersection numbers. It is also proved that asymptotically, this condition is also sufficient. More precisely, an arbitrary homogeneous coherent configuration satisfying this condition is associated with a transitive group, the point stabilizer of which is a TI-subgroup. As a byproduct of the developed theory, recent results on pseudocyclic and quasi-thin association schemes are generalized and improved. In particular, it is shown that any scheme of prime degree \(p\) and valency \(k\) is associated with a transitive group, whenever \(p > 1 + 6 k(k - 1)^2\).

MSC:

05E30 Association schemes, strongly regular graphs
20B99 Permutation groups

Software:

GAP

References:

[1] Brouwer, A. E.; Cohen, A. M.; Neumaier, A., Distance-Regular Graphs, Ergebnisse der Mathematik und ihrer Grenzgebiete (3), vol. 18 (1989), Springer-Verlag: Springer-Verlag Berlin etc. · Zbl 0747.05073
[2] Busarkin, V. M.; Gorchakov, Yu. M., Finite Decomposable Groups (1968), (in Russian)
[3] Evdokimov, S.; Ponomarenko, I., Permutation group approach to association schemes, European J. Combin., 30, 1456-1476 (2009) · Zbl 1228.05311
[4] Evdokimov, S.; Ponomarenko, I., On coset closure of a circulant S-ring and schurity problem, J. Algebra Appl., 15, 4 (2016), 49 pp · Zbl 1333.05321
[5] GAP - Groups, Algorithms, and Programming (2016), Version 4.8.2
[6] Hanaki, A.; Uno, K., Algebraic structure of association schemes of prime order, J. Algebraic Combin., 23, 189-195 (2006) · Zbl 1089.05081
[7] Hochheim, Y.; Timmesfeld, F., A note on TI-subgroups, Arch. Math., 51, 97-103 (1988) · Zbl 0666.20009
[8] Kim, K., A family of non-Schurian \(p\)-Schur rings over groups of order \(p^3\), J. Group Theory, 19, 4, 617-633 (2016) · Zbl 1371.20003
[9] Muzychuk, M., A wedge product of association schemes, European J. Combin., 30, 705-715 (2009) · Zbl 1207.05224
[10] Muzychuk, M.; Ponomarenko, I., On pseudocyclic association schemes, Ars Math. Contemp., 5, 1, 1-25 (2012) · Zbl 1242.05281
[11] Muzychuk, M.; Ponomarenko, I., On quasi-thin association schemes, J. Algebra, 351, 467-489 (2012) · Zbl 1244.05236
[12] Ponomarenko, I.; Vasil’ev, A., Cartan coherent configurations, J. Algebraic Combin., 45, 2, 525-552 (2017) · Zbl 1436.20054
[13] Williams, J. S., Prime graph components of finite groups, J. Algebra, 69, 487-513 (1981) · Zbl 0471.20013
[14] Zieschang, P.-H., Theory of Association Schemes (2005), Springer: Springer Berlin, Heidelberg · Zbl 1079.05099
This reference list is based on information provided by the publisher or from digital mathematics libraries. Its items are heuristically matched to zbMATH identifiers and may contain data conversion errors. In some cases that data have been complemented/enhanced by data from zbMATH Open. This attempts to reflect the references listed in the original paper as accurately as possible without claiming completeness or a perfect matching.