已知数列{an}的前n项和为Sn,且对任意正整数n,有Sn、an、n成等差数列
已知数列{an}的前n项和为Sn,且对任意正整数n,有Sn、an、n成等差数列
已知数列{an}的前n项和为Sn,且对任意n属于N ,有n,an,Sn成等差数列.
已知数列{an}的首项为a1=1,其前n项和为sn,且对任意正整数n有:n、an、Sn成等差数列.
已知数列{an}的前n项和为Sn,且对任意正整数n都有an是n与Sn的等差中项.
设数列{an}的前n项和为Sn,且对任意正整数n,an+Sn=4096
设数列{an}的前n项和为Sn,且对任意正整数n,an+Sn=4096.
设数列{an}的前n项和为Sn,若对任意正整数,都有Sn=n(a1+an)/2,证明{an}是等差数列.
已知数列{an}的前n项和为Sn,且对任意正整数n,有Sn,a/2(a-1),n(a不等于0,a不等于1)成等差数列,令
已知等差数列an的首项a1为a,设数列的前n项和为Sn,且对任意正整数n都有a2n/an=4n-1/2n-1,求数列的通
已知正整数数列an的前n项和为sn,且对任意的正整数n满足2根号下2sn=an+2求证an是等差数列
在数列{an}中前n项和为Sn,且对任意正整数n,an+sn=2048
已知数列{an}的前n项和为Sn,且对任意的n∈N*有an+Sn=n.