Dear Abdulsatar, I do not quite understand your question. I suppose that you want to know whether the two groups specified by both presentations are isomorphic. But you say that both presentations are of the same group, namely the automorphism group of the free Abelian group of rank n. If that is so, then obviously both groups are isomorphic, since they are the same group !!
On the other hand, if you want to know, for two arbitrary presentations P_1 and P_2, whether the corresponding groups G_1 and G_2 are isomorphic, then it is impossible in general. This is one of the three problems stated by Max Dehn in 1911, which turned out to be unsolvable. The other two are the word problem and the conjugacy problem. It is possible, however, to solve the problem for some special classes of presentations. I hope this answers your questions. Best regards, Hebert Perez-Roses The University of Lleida, Spain 2013/2/25 Abdulsatar Al-Juburie <a.j.t.al-jubu...@newcastle.ac.uk>: > Dear Forum, > > I got by using GAP two presentations for the automorphism of group of the > free Abelian group of rank n. . However, I ask if there is any way in GAP to > let me know if these two presentations are isomorphic. > > I would be appreciated if you could help me in this matter. > > Best Regards, > > Abdulsatar > > > > > _______________________________________________ > 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
