The binary tetrahedral group has order 24, but the "Tetra" group as defined here: http://doc.sagemath.org/html/en/reference/groups/sage/groups/matrix_gps/finitely_generated.html has order 48.
sage: K.<i> = CyclotomicField(4) sage: Tetra = MatrixGroup([(-1+i)/2,(-1+i)/2, (1+i)/2,(-1-i)/2], [0,i, -i,0]) sage: Tetra Matrix group over Cyclotomic Field of order 4 and degree 2 with 2 generators ( [ 1/2*i - 1/2 1/2*i - 1/2] [ 0 i] [ 1/2*i + 1/2 -1/2*i - 1/2], [-i 0] ) sage: len(Tetra) 48 So it looks like another rep of the Octahedral group. Simon. -- You received this message because you are subscribed to the Google Groups "sage-devel" group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-devel+unsubscr...@googlegroups.com. To post to this group, send email to sage-devel@googlegroups.com. Visit this group at https://groups.google.com/group/sage-devel. For more options, visit https://groups.google.com/d/optout.
