数列{an}的前n项和为Sn,Sn=1-23
数列{an}的前n项和为Sn,Sn=1-23
已知数列{an}的前n项和为Sn,a1=-23,Sn+1Sn=an-2(n≥2,n∈N)
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
已知数列{an}的前n项和为Sn,且Sn=23an+1(n∈N*);
数列{an}的前n项和为Sn,a1=1,an+1=2Sn(n∈N*)
已知数列{an}的前n项和为Sn,Sn=(an-1)/3 (n∈N)
数列{an}的前n项和为Sn,且Sn=13(an−1)
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
设数列{an}的前N项和为Sn,已知1/Sn+1/S2+1/S3+.+1/Sn=n/(n+1),求Sn
数列{an}前n项和为Sn,且2Sn+1=3an,求an及Sn
设数列{an}的前n项和为Sn,且Sn=2^n-1.