已知数列{an}满足a1=1,Sn=[(n+1)/2]*an,求通项an.急,思路也要
已知数列{an}满足a1=1/2,sn=n^2an,求通项an
已知数列an满足a1=1/2 sn=n平方×an 求an
已知数列{an},满足a1=1/2,Sn=n²×an,求an
已知数列{an}a1=2前n项和为Sn 且满足Sn Sn-1=3an 求数列{an}的通项公式an
已知数列an中,a1=1,前项n和sn与通项an满足an=2sn2/2sn-1,求通项的an表达式
已知数列{an}满足an+1+an=4n-3 当a1=2时,求Sn
已知数列{an}满足,a1=2,a(n+1)=3根号an,求通项an
已知数列{an}满足an+1=2an+3.5^n,a1=6.求an
已知数列An的前n项和Sn满足An+2Sn*Sn-1=0,n大于等于2,A1=1/2,求An.
已知数列an首相a1=3,通项an和前n项和SN之间满足2an=Sn*Sn-1(n大于等于2)
已知数列{an}的前n项的和Sn,满足6Sn=an2+3an+2且an>0.(1)求首项a1;(2)证明{an}是
已知数列(An)满足A1=1 An+1=3An 数列(Bn)前n项和Sn=n*n+2n+1