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A tight upper bound on the order of a finite subgroup of the collineation group of the free projective plane F_n.
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%I #11 Jun 20 2022 11:25:33

%S 24,12,120,240,1440,10080,80640,725760,7257600,79833600,958003200,

%T 12454041600,174356582400,2615348736000,41845579776000,

%U 711374856192000,12804747411456000,243290200817664000,4865804016353280000,102181884343418880000,2248001455555215360000,51704033477769953280000,1240896803466478878720000

%N A tight upper bound on the order of a finite subgroup of the collineation group of the free projective plane F_n.

%H Oddvar Iden and Jan G. Moe, <a href="https://doi.org/10.1007/BF00181632">Automorphism groups of free Moebius planes and free Laguerre planes</a>, Geometriae dedicata 7.2 (1978): 209-222.

%F Equals 2*(n-2)! for n = 5 and n >= 7.

%F E.g.f.: x*(60 - 30*x - 10*x^2 + 25*x^3 + 3*x^5)/30 + 2*(1 - x)*log(1 - x). - _Stefano Spezia_, Jun 21 2021

%K nonn

%O 4,1

%A _N. J. A. Sloane_, Jun 21 2021