Innovations in Incidence Geometry

An alternative existence proof of the geometry of Ivanov-Shpectorov for O'Nan's sporadic group

Francis Buekenhout and Thomas Connor

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We provide an existence proof of the Ivanov–Shpectorov rank 5 diagram geometry together with its boolean lattice of parabolic subgroups and establish the structure of hyperlines.

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Innov. Incidence Geom., Volume 15, Number 1 (2017), 73-121.

Received: 25 November 2014
Accepted: 16 December 2016
First available in Project Euclid: 28 February 2019

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incidence geometry diagram geometry Buekenhout diagrams O'Nan's sporadic group


Buekenhout, Francis; Connor, Thomas. An alternative existence proof of the geometry of Ivanov-Shpectorov for O'Nan's sporadic group. Innov. Incidence Geom. 15 (2017), no. 1, 73--121. doi:10.2140/iig.2017.15.73.

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