已知等差数列[An],Sn=[（An+1）/2]^2,求An的通项公式n为下标,求救啊!

已知数列an,an属于n*,sn=1/8*(an+2)^2,{an}是等差数列 已知等差数列{an},a10?Sn 已知等差数列{an}中,a1=-60,an+1=an+3,求Sn=|a1|+|a2|+…+|an| 已知数列{an},an属于自然数,sn=1/8(an+2)^2.求｛an}是等差数列 (1)已知数列an的前n项和为sn满足sn=an²+bn,求证an是等差数列(2)已知等差数列an的前n项和为sn,求证数列sn/n也成等差数列 已知数列{An},Sn=0.125（An+2)(An+2).求证：{An}是等差数列 在等差数列中,已知d=2,an=1,sn=8求an,n 已知等差数列{an}的通项公式an=2n+1,求Sn 已知Sn=1/8(an+2)^2 证：{an}是等差数列 已知公差不为0的等差数列{An}的首项A1=1,前n项和为Sn,若数列{Sn/An}是等差数列,求An? 已知数列{an}中,a2=2,前n项和为Sn,且Sn=n(an+1)/2证明数列{an+1-an}是等差数列 已知数列{an}中,an>0其前n项和为Sn,且Sn=1/8(an+2)²,求证：数列{an}为等差数列 已知数列{an}中,an>0,前n项和为Sn,且满足Sn=1/8(an+2)^2.求证数列{an}是等差数列. 已知{an}为等差数列,Sn为其前n项喝,且2Sn=an+2n²(1)求an.Sn 已知数列an前n项和sn=n平方＋1an前五项?是否等差数列?an通向公式 求此数列题详细解法已知数列an Sn=1/8(an+2)^2 求证an是等差数列 已知{an}是等差数列,a1+a2+a3+a4=11,an-3+an-2+an-1+an=67且sn=286求项数n?题目没错！ 在数列{An}中,已知A1=1,An=2Sn^2/(2Sn-1),(n>=2),证明{1/Sn}是等差数列,并求Sn