设数列An的前n项和Sn=2An-2n的次方,求A1,A4
设数列An的前n项和Sn=2An-2n的次方,求A1,A4
设数列an的前n项和sn=2an-2^n 求a3 a4
设数列{an}的前n项和Sn=2an-2^n,1;求a3,a4
设数列{an}的前n项和为sn,sn=a1(3^n-2)/2(n≥1),a4=54,则a1=
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,
关于数列的设数列{an}的前n项和为Sn,且满足an=2-Sn(n∈N*) 求a1,a2,a3,a4的值并写出其通项公式
设数列{an}的前n项和为Sn,a1=1,Sn=nan-2n(n-1) (1)求a2,a3,a4,并求出数列{an}的通
设数列{an}的前n项和为Sn,且a1=1,Sn=nan-2n(n-1) (1)求a2,a3,a4,并求出数列{an}的
设数列{an}的前n项和为Sn,a1=1,且3a(n+1)=Sn,(1)求a2,a3,a4及an (2)求a2+a4+·
设数列{An}的前n项和Sn=2a-2n平方.1求a3,a4
设数列An的前n项和Sn=2An-2^n 求A3,A4 证明A(n+1)-2An为等比
已知数列{An}的前n项和为Sn,且Sn+An =2n.求a1.a2.a3.a4.