设Sn为等比数列{an}的前n项和,若a1=1,且2a2,S3,a4+2成等差数列,则数列{an2}的前5项和( )
设Sn为等比数列{an}的前n项和,若a1=1,且2a2,S3,a4+2成等差数列,则数列{an2}的前5项和( )
等差数列{an}的前n项和为Sn,设S3=12,且2a1,a2,a3 1成等比数列,求Sn?
等差数列an的前n项和为Sn,设S3=122,且2a1.a2.,a3+1成等比数列,求Sn
记等差数列{an}的前n项和为Sn,设S3=12,且2a1,a2,a3+1成等比数列,求Sn.
1.已知等差数列{an}的前n项和为Sn,若S3=12,且2a1,a2,a3+1成等比数列求 Sn
已知等差数列{an}前n项和为Sn,公差d≠0,且S3+S5=50,a1,a4,a13,成等比数列 (2)若从数列
20、已知正向等差数列{an}的前n项和为Sn,若S3=12,且2a1,a2,a3+1成等比数列.
已知正向等差数列{an}的前n项和为Sn,若S3=12,且2a1,a2,a3+1成等比数列.
设数列{an}的前n项和为Sn,且an不等于0,S1,S2,S3 Sn成等比数列,试问a1,a2,a2是等比数列吗
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
一道高中数列题,..已知正项等差数列{an}的前n项和为Sn,若S3=12,且2a1,a2,a3+1成等比数列.求{an
记等差数列{an}的前n项和为sn,s3=12,且2a1,a2,a3+1成等比数列,求