`数列{an}的前n项和为Sn,a1=2,na(n+1)=Sn+n(n+1)(n∈N+)(1)求an,Sn(2)设Tn=1/S1+1/S2+...+1/Sn,求Tn的值

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`数列{an}的前n项和为Sn,a1=2,na(n+1)=Sn+n(n+1)(n∈N+)(1)求an,Sn(2)设Tn=1/S1+1/S2+...+1/Sn,求Tn的值

`数列{an}的前n项和为Sn,a1=2,na(n+1)=Sn+n(n+1)(n∈N+)(1)求an,Sn(2)设Tn=1/S1+1/S2+...+1/Sn,求Tn的值
`数列{an}的前n项和为Sn,a1=2,na(n+1)=Sn+n(n+1)(n∈N+)
(1)求an,Sn
(2)设Tn=1/S1+1/S2+...+1/Sn,求Tn的值

`数列{an}的前n项和为Sn,a1=2,na(n+1)=Sn+n(n+1)(n∈N+)(1)求an,Sn(2)设Tn=1/S1+1/S2+...+1/Sn,求Tn的值
m

an=2n

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