C31:=PermutationGroup<24|(1, 3, 10)(2, 15, 21)(4, 16, 17)(5, 14, 18)(6, 19, 7)(8, 11, 13)(9, 23,12)(20, 24, 22)>;


print("a defect group C31 of the 3-blocks B_2, B_3, B_5 of M24");