a2+a4=a1+a5 =10
a5=9,得a1=1
a5=a1+4d=9,得d=2
an=a1+(n-1)d=2n-1
Sn=n(a1+an)/2=n^2
bn+1=bn+an
bn=b(n-1)+a(n-1)
=b(n-2)+a(n-2)+a(n-1)
.............
=b1+a1+a2+...+a(n-1)
=(n-1)^2+1
Cn=2/(2n-1)(2n+1)=1/(2n-1)-1/(2n+1)
Tn= c1+c2+...+cn
=2/(1*3)+2/(3*5)+...+2/(2n-1)(2n+1)
=1-1/3+1/3-1/5+...+1/(2n-1)-1/(2n+1)
=1-1/(2n+1)
=2n/(2n+1)
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