已知数列﹛an﹜的前n项和为Sn,a1=1,且2nSn+1-2(n+1)Sn=n²+n(n∈N*).(1)求数列{an}的通项公式;(2)设bn=n/2(n+3)Sn,求数列{bn}的前n项和Tn;(3)证明:n≥2时,1/(a2的三次方)+1/(a3的三次方)+1/(a4的三次方)+……+1/(an的三次方)<1/4
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已知数列﹛an﹜的前n项和为Sn,a1=1,且2nSn+1-2(n+1)Sn=n²+n(n∈N*).(1)求数列{an}的通项公式;(2)设bn=n/2(n+3)Sn,求数列{bn}的前n项和Tn;(3)证明:n≥2时,1/(a2的三次方)+1/(a3的三次方)+1/(a4的三次方)+……+1/(an的三次方)<1/4
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