## Innovations in Incidence Geometry

### Flag-transitive and almost simple orbits in finite projective planes

Alessandro Montinaro

#### Abstract

Let $Π$ be a projective plane of order $n$ and let $G$ be a collineation group of $Π$ with a point-orbit $O$ of length $v$. We investigate the triple $(Π,O,G)$ when $O$ has the structure of a non trivial $2$-$(v,k,1)$ design, $G$ induces a flag-transitive and almost simple automorphism group on $O$ and $n≤∑(O)=b+v+r+k$.

#### Article information

Source
Innov. Incidence Geom., Volume 8, Number 1 (2008), 1-37.

Dates
Accepted: 15 January 2008
First available in Project Euclid: 28 February 2019

https://projecteuclid.org/euclid.iig/1551323141

Digital Object Identifier
doi:10.2140/iig.2008.8.1

Mathematical Reviews number (MathSciNet)
MR2658656

Zentralblatt MATH identifier
1202.51007

#### Citation

Montinaro, Alessandro. Flag-transitive and almost simple orbits in finite projective planes. Innov. Incidence Geom. 8 (2008), no. 1, 1--37. doi:10.2140/iig.2008.8.1. https://projecteuclid.org/euclid.iig/1551323141

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