8 papers
On the density of Sylow numbers
Andrea Lucchini, Pablo Spiga
Let be a prime number. We say that a positive integer is a Sylow -number if there exists a finite group having exactly Sylow -subgroups. When , every odd int…
Finite simple groups have many classes of prime order elements
Jessica Anzanello, Pablo Spiga
Let be a finite non-abelian simple group. Giudici, Morgan and Praeger have shown that the order of is bounded above by a function depending on the maximum number of $\mathr…
Normal 2-coverings in affine groups of small dimension
Marco Fusari, Andrea Previtali, Pablo Spiga
A finite group admits a normal -covering if there exist two proper subgroups and with . For determining inductively the…
On the base size and minimal degree of transitive groups
Lorenzo Guerra, Attila Maróti, Fabio Mastrogiacomo +1
Let be a permutation group, and denote with and its minimal degree and base size respectively. We show that for every , there exists a transitive p…
The maximal rank of a string group generated by involutions for alternating groups
Jessica Anzanello, Maria Elisa Fernandes, Pablo Spiga
A string group generated by involutions, or SGGI, is a pair , where is a group and is an ordered set of involutions generating and sat…
Counting subgroups of a finite group containing a prescribed subgroup
Lorenzo Guerra, Fabio Mastrogiacomo, Pablo Spiga
Let be a finite group, and let be a subgroup of . We show that there are at most \[ 7.3722[R:T]^{\frac{\log_2[R:T]}{4}+1.8919} \] subgroups of containing .