Abstract
The Harada-Norton group HN is a sporadic simple group of order 273030912000000 equal to 2(14) x 3(6) x 5(6) x 7 x 11 x 19. It has 14 conjugacy classes of maximal subgroups and in the present paper we construct the Fischer-Clifford matrices and hence character table for one of these maximal subgroups, that is the non-split extension 2(6).U-4(2), of index 164587500. There is not that many known examples of the application of Fischer-Clifford theory to non-split extensions, and hence this maximal subgroup of Hard-Norton's group serves as a good candidate. Most of the computations were carried out using the computer algebra systems GAP [10] and MAGMA [4].