Dear Jianjun, dear forum, Adolfo Ballester-Bolinches and I are preparing a GAP package to check permutability of subgroups in finite groups and to decide whether a finite has all subnormal subgroups normal or permutable, among other things. According to a result of Iwasawa, these groups are nilpotent and have a Sylow p-subgroup P which satisfies one of the following two conditions: - P is a direct product of a quaternion group of order 8 and an elementary abelian 2-group, or - P has an abelian normal subgroup A and an element b such that $P=A\langle b\rangle$ and there exists a natural number s, which is greater than 1 if p=2, such that a^b=a^{1+p^s} for all a in A.
The package includes functions which perform this test. The package is almost finished, we are making the final revision of the package and the documentation. We hope to submit it soon to be refereed. We can send you a preliminary version of the package if you want. With best wishes, -- Ramon <reste...@mat.upv.es> Clau pública PGP/Llave pública PGP/Clef publique PGP/PGP public key: http://www.rediris.es/cert/servicios/keyserver/ http://personales.upv.es/~resteban/resteban.asc Telèfon/teléfono/téléphone/phone: (+34)963877007 ext. 76676 * 刘建军 <ljj198...@126.com> [110713 19:29]: > Dear forum, > > A subgroup H of a finite group G is said to be permutable if HK=KH for every > subgroup K of G. > > I would like to know whether all subgroups of a group G are permutable. > Is there a method to get it in GAP? > > Best Wishes > Jianjun Liu > _______________________________________________ > Forum mailing list > Forum@mail.gap-system.org > http://mail.gap-system.org/mailman/listinfo/forum _______________________________________________ Forum mailing list Forum@mail.gap-system.org http://mail.gap-system.org/mailman/listinfo/forum