Dear Rashid, I was just uploading a new version of HAP 1.7.3 when your e-mail arrived. So I have included a quickly written function NonabelianTensorProduct(G,N) which inputs a finite group G and normal subgroup N. It returns a record with the homomorphism delta:G\otimes N --> G and the crossed pairing h:G\times N --> G . I'll improve the efficiency of this function in the next release.
To calculate the order of the tensor product G\otimes N where G is the Sylow 2-subgroup of the Mathieu group M12, and N the derived subgroup of G, you need to type the following: gap> G:=SylowSubgroup(MathieuGroup(12),2);; gap> N:=DerivedSubgroup(G);; gap> T:=NonabelianTensorProduct(G,N);; gap> TensProd:=Source(T.homomorphism); gap> Order(TensProd); 128 All the best, Graham -----Original Message----- From: [EMAIL PROTECTED] on behalf of rashid rezaei Sent: Sun 11/03/2007 14:41 To: [EMAIL PROTECTED] Subject: [GAP Forum] question Dear Forum, I am looking for computing the non-abelian tensor product $G\otimes N$ where $N$ is a normal subgroup of $G$. I found the command for tensor square in the package HAP, but I could not find any similar for $G\otimes N$. I will be more grateful for any help or comments. Regards, R. Rezaei. Send instant messages to your online friends http://uk.messenger.yahoo.com _______________________________________________ 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
