(1)bn=1+(n-1)*2=2n-1
Sn=n(2n-1)
当n>2orn=2时:an=Sn-Sn-1=4n-3
n=1时a1=S1=1
所以an=4n-3
(2)Cn=1/[(4n-3)(4n+1)]=(1/4)*{1/(4n-3)-1/(4n+1)}
Tn=(1/4)*[1-1/(4n+1)]
(1)bn=1+(n-1)*2=2n-1
Sn=n(2n-1)
当n>2orn=2时:an=Sn-Sn-1=4n-3
n=1时a1=S1=1
所以an=4n-3
(2)Cn=1/[(4n-3)(4n+1)]=(1/4)*{1/(4n-3)-1/(4n+1)}
Tn=(1/4)*[1-1/(4n+1)]