Characterization of affine Steiner triple systems and Hall triple systems
نویسندگان
چکیده
It is known that a Steiner triple system is projective if and only if it does not contain the four-triple configuration C14. We find three configurations such that a Steiner Electronic Notes in Discrete Mathematics 29 (2007) 17–21 1571-0653/$ – see front matter © 2007 Elsevier B.V. All rights reserved. www.elsevier.com/locate/endm doi:10.1016/j.endm.2007.07.004 triple system is affine if and only if it does not contain any of these configurations. Similarly, we characterize Hall triple systems, a superclass of affine Steiner triple systems, using two forbidden configurations.
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عنوان ژورنال:
- Electronic Notes in Discrete Mathematics
دوره 29 شماره
صفحات -
تاریخ انتشار 2007