已知等差数列{an}的前n项的和为Sn,若a4/a16=-1/2,则使Sn=0的n的值是
已知等差数列{an}的前n项的和为Sn,若a4/a16=-1/2,则使Sn=0的n的值是
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
已知等差数列{an}的前n项和为Sn,如果Sn=(an+1/2)^2(n∈N+0,bn=(-1)^n*Sn
已知数列{an}的前n项和为Sn,且满足Sn=Sn-1/2Sn-1 +1,a1=2,求证{1/Sn}是等差数列
已知Sn为等差数列an的前n项和 a1=25 a4=16
已知等差数列An前n项和是Sn,若A3=10,则求A4的最大值为
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?
已知等差数列{an}的前n项和为Sn,且(2n-1)Sn+1 -(2n+1)Sn=4n²-1(n∈N*)
等差数列{An}的前n项和为Sn,若 lim Sn/n方 =2
已知等差数列{an}满足:a3+a4=16,a4+a5=20,{an}的前n项和为Sn
已知等差数列{an}的前n项和为Sn,且a1不等于0,求(n*an)/Sn的极限、(Sn+Sn+1)/(Sn+Sn-1)
等差数列{An},{Bn}的前n项和为Sn与Tn,若Sn/Tn=2n/3n+1,则An/Bn的值是?