When n= 1, a1= (4/3) (a1-1).

a 1=4

When n≥2, an = sn-s (n-1) = (4/3) (an-1)-(4/3) [a (n-1)-1].

An/a(n- 1)=4, which is a fixed value. The sequence {an} is a geometric series with 4 as the first term and 4 as the common ratio.

an=4 4？ =4?

The general formula of the sequence {an} is an=4?

(2)

bn=log2(an)=log2(4？ )=2n

1/[(bn- 1)(bn+ 1)]= 1/[(2n- 1)(2n+ 1)]=？ [ 1/(2n- 1)- 1/(2n+ 1)]

Tn=？ [ 1/ 1 - 1/3 + 1/3 - 1/5+...+ 1/(2n- 1)- 1/(2n+ 1)]

=? [ 1- 1/(2n+ 1)]

=? - 1/(4n+2)

1/(4n+2)>0,? - 1/(4n+2)& lt； ?

Tn & lt？