`A_1 = [a_1] , A_2=[[a_2 , a_3],[a_4 ,a_5]] , A_3=[[a_6,a_7,a_8],[a_9,a_10,a_11],[a_12,a_13,a_14]]............................A_n=[..........]`where `a_r=[log_2r] ([.]` denotes greatest integer `)` then trace of `A_10`