设一列数1,1/2,1/4,1/8.1/2的n-1次方的和为Sn,Sn的值为
设Sn为数列{an}的前n项和,an=1+2+2的平方+ +2的n-1次方,则Sn的值为?
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,则公比q为( )
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=?
设数列an的前n项和为Sn,已知Sn=2an-2的[N+1]次方求an的通项公式
设数列an的前n项和为Sn,已知a1=1,Sn+1=4an+2
设数列an的首项a1等于1,前n项和为sn,sn+1=2n
设 数列{an}的前n项和为Sn,已知b*an - 2^n=(b-1)Sn
设数列(An)的前N项和为Sn,已知Sn=2An-2的n次方.(1)设(Bn)=an/2的n次方-1,证明(Bn)为等差
设数列{an}的前n项和为Sn,若a1=1,Sn=2an+Sn+(n∈N+),则a6=
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
设数列{an}的前n项和为Sn,满足2Sn=an+1-2^n+1+1,且a1,a2+5.a3成等差数
设数列an中的前n项的和为Sn,并且a1=1,Sn+1=4an+2,设bn=an比2的n次方,求证数列bn为等差数列