Sn = a1+a2+..+an
Sn =n^2 (1)
S(n-1) = (n-1)^2 (2)
(1) -(2)
an = 2n-1
consider
1/(ana(n+1))
=1/[(2n-1)(2n+1)]
=(1/2)[ 1/(2n-1) -1/(2n+1)]
Tn=1/(a1a2)+1/(a2a3) +..+1/(ana(n+1))
=(1/2)[ (1-1/3) + (1/3-1/5) +...+(1/(2n-1)-1/(2n+1) ]
= (1/2)(1- 1/(2n+1)]
= n/(2n+1)
Sn = a1+a2+..+an
Sn =n^2 S(n-1) = (n-1)^2 (1) -(2)
an = 2n-1
consider
1/(ana(n+1))
=1/[(2n-1)(2n+1)]
=(1/2)[ 1/(2n-1) -1/(2n+1)]
Tn = n/(2n+1)
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