设等比数列{an}的前n项和为Sn,已知an+1=2sn+2
设Sn是等比数列{an}的前n项和,且Sn=2an+n
设等比数列{an}的前n项和为sn,已知an+1=2sn+2(n属于正整数).1》求数列的通项公式
设等比数列{an}的前n项和为sn,已知an+1=2sn+2(n属于正整数).1》求数列的通项公式 0 |
设等比数列{an}的前n项和为Sn,已知a1=2011,且an+2an+1+an+2=0(N∈N*),则S2012?
数列An的前n项和为Sn,已知A1=1,An+1=Sn*(n+2)/n,证明数列Sn/n是等比数列
已知等比数列{an}的公比为q,前n项和为Sn,求[Sn*Sn+2-(Sn+1)^2]/[an*an+2]
设等比数列{an}的公比为q,前n项和为Sn,若Sn+1,Sn,Sn+2成等差数列,则q=?
设Sn为等比数列{an}的前n项和,已知Sn=3an+1+m,Sn-1=3an+m,则公比q=
设 数列{an}的前n项和为Sn,已知b*an - 2^n=(b-1)Sn
设等比数列An的前n项和为Sn,对任意正整数n,都有An+1=2Sn-1,求通项公式An
等比数列中,sn为前n项和,sn=2an—1,求an
设等比数列{an}的公比为q,前n项和为Sn,若Sn+1,Sn,Sn+2成等差数列,则q等于多少?若an=1,求sn前n