数列an是等差数列,首项不为0,求lim(n*an/Sn)

已知数列an是等差数列,且a1≠0,Sn为这个数列的前n项和.求1、lim nan/Sn 2、lim (Sn+Sn+1) 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是等差数列,且a1不等于0,Sn为这个数列的前n项和,求limnan/Sn.limSn+Sn-1/Sn+Sn {an}为等差数列,公差d>0,Sn是数列{an}前n项和, 高中数学有关数列、极限的题：设等差数列{an}的公差d=2,前n项的和为sn,则lim(an^-n^0/sn= 已知数列an的前n项和为Sn,且an+2Sn*Sn-1=0,a1=1/2,求证1/SN是等差数列,求数列SN的的通项公式 数列前n项和为sn,a1=1,an+sn是公差为2的等差数列,求an-2是等比数列,并求sn 求极限,数列An是等差数列,且A1不等于0,Sn是前N项和 数列{an}是等差数列,公差为3,an=11,sn=14,求n和a3,要步骤. 数列{an}是等差数列,公差为3,an=11,sn=14,求n和a3, 已知数列{an}的前n项和为Sn,且满足an+2Sn*Sn-1=0,a1=1/2.求证：{1/Sn}是等差数列 已知数列{an}是等差数列,公差d>0,前n项和Sn=【(an+1)/2】^2,bn=(-1)^n*Sn,求数列{bn}