Given the sum of the first n terms of the sequence {an} Sn = - 3 / 2n & sup2; + 205 / 2n, find the general term formula of the sequence {an}
an=Sn-S(n-1)=-3/2n²+205/2n+3/2(n-1)²-205/2(n-1)=(-3+205n)/2n²+(208-205n)/2(n-1)²
=(-205n^2+211n-3)/2 n²(n-1)²
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