设数列{an}的前几项和为Sn,a1=10 an+1=9Sn+10 求证{lgan}是等差数列

设数列{an}的前几项和为Sn,a1=10 an+1=9Sn+10 求证{lgan}是等差数列 已知数列{An}前n项和为Sn,A1=10,A（n+1）=9Sn+10.1,求证{lgAn}是等差数列. 设数列{an}的前n项和为sn,a1=10,an+1=9sn+10.设Tn是数列（3/（lgan)(lgan+1)}的前 设数列an的前n项和为Sn,a1=1,an=(Sn/n)+2(n-1)(n∈N*) 求证:数列an为等差数列, 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}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 设数列an的前n项和为sn,对于所有的自然数n都有sn=n(a1+an)/2,求证an是等差数列 设数列{an}的前n项和为Sn,a1=1,an=sn/n+2(n-1),求证数列{an}是等差数列,并求其通项公式an 设数列An的前n项和为Sn,已知a1=1,An+1=Sn+3n+1求证数列｛An+3}是等比数列 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 设数列{an}的前项和为Sn,且a1=1,Sn+1=4a2+2.设Cn=an/2^n,求证：数列{cn}是等差数列 设数列{an}的前n项和为Sn,a1=10,a(n+1)=9Sn+10