[挑戰]級數hk

香港級數問題 

Let {xn} be a sequence of positive real number, If x1 = 3/2 and xn+12 – xn2 = 1/(n+2)2 – 1/n2 for all positive integers n, find x1 + x2 + x3 + … + x2008

(xn+1)^2 – xn^2 = 1/(n+2)^2 – 1/n^2 

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