Supported by the Tianyuan Fund for Mathematics of NSFC(11126273);Supported by the NSF of Henan Educational Committee(2011B110011);Supported by the Doctor Foundation of Henan University of Technology(2009BS029)
In this paper,the automorphism group of G is determined,where G is a 4 × 4 upper unitriangular matrix group over Z.Let K be the subgroup of AutG consisting of all elements of AutG which act trivially on G/G,G /ζG a...