设等差数列{an}的前n项和为Sn,a1=3/2,且S1,S2,S4成等差数列,求Sn
设等差数列an的前n项和为Sn,a1=3/2,且s1,s2,s4成等比数列,求sn
已知等差数列{an}的首项a1=a,公差d=2,前n项和为Sn,且S1,S2,S4成等比数列
设Sn是公差不为0的等差数列an地前n项和且S1,S2,S4成等比数列,则a1/a2等于
若Sn是公差不为0的等差数列an的前n项和,且S1,S2,S4成等比数列,求数列S1,S2,S4的公比
已知等差数列an的公差为2,前n项和为sn,且s1,s2,s4成等比数列
已知等差数列{an}的公差为2,前n项和为sn,且s1,s2,s3,s4成等比数列
设数列{an}是首项为a1(a1>0),公差为2的等差数列,前n项和为Sn,且根号S1,根号S2,根号S3成等差数列,
设Sn是公差不为0的等差数列an的前n项和,且S1,S2,S4成等比数列.(1)求a
已知等比数列{an}的前n项和为Sn,若S1,2S2,3S3成等差数列,且S4=4027
已知等差数列{an}的公差为2,前n项和为Sn,且S1,S2,S4成等比数列. (Ⅰ)求数列{an
若Sn是公差不为0的等差数列{An}的前n项和,且S1,S2,S4成等比数列.an=2n-1.设bn=3/[an*a(n
等差数列{an}的前n项和为Sn.已知S3=a22,且S1,S2,S4成等比数列,求{an}的通项式.