等比数列{an}的前n项和为Sn a4=8 S(n+1)=pSn+1 p为
等比数列{an}的前n项和为Sn a4=8 S(n+1)=pSn+1 p为
设等比数列an的公比为q=1/2,前n项和为Sn,则S4/a4=?
等比数列an的前n项和为sn,sn=1+3an,求:an
设an公差不为0的等差数列.(1)前n项和为Sn,Sn=110,a1.a2.a4为等比数列.求an通项公式.
设等比数列{an}的公比q=1/2,前n项和为Sn,则S4/a4=
设等比数列an的公比q=1/2,前n项和为sn,则s4/a4=
设等比数列{an}的公比q=1/2,前n项和为Sn,则S4/a4=?
设等比数列an的公比q=1/2,前n项和为Sn,则S4/a4
设等比数列 {an} 的公比为q,前n项和为Sn,若S(n+1),Sn,S(n+2)成等差数列,则q=
已知公差不为0的等差数列an的前n项和为Sn,S3=a4+6,且a1 a4 a13成等比数列,求数列1/Sn的前n项和公
等比数列中,sn为前n项和,sn=2an—1,求an
已知数列{an}的前n项和为Sn,且Sn=n-5an-85,n∈N*,证明{an-1}为等比数列