(Ⅰ)∵{an}是首项为a1=
,公比q=1 4
的等比数列,1 4
∴an=(
)n,bn+2=3log1 4
an(n∈N*)=3log1 4
(1 4
)n=3n,1 4
∴bn=3n-2.
(Ⅱ)cn=
=3
bn?bn+1
=3 (3n?2)(3n+1)
?1 3n?2
,1 3n+1
∴Tn=(1?
)+(1 4
?1 4
)+…+(1 7
?1 3n?2
)1 3n+1
=1?
.1 3n+1