Sn是等差数列1,3,5的前n项和,则limSn/S2n

Sn是等差数列1,3,5的前n项和,则limSn/S2n 等比数列{an}中若a1=1,且前N项和SN构成等差数列,则等差数列{sn}的公差是?且前N项和SN构成等差数列,这句怎么理解..请详细给出解题思路3Q Sn是等差数列的前n项和,{Sn/n}是等差数列吗? Sn是等差数列的前n项和,{Sn/n}是等差数列吗? 设Sn为等差数列{An}的前n项和,求证：{Sn/n}是等差数列 等差数列{An},{Bn}的前n项和为Sn与Tn,若Sn/Tn=2n/3n+1,则A5/B7的值是 等差数列{an},{bn}的前n项和分别为Sn,Tn,Sn/Tn=2n/3n+1则a3/b5是a3/b5不是其他 设等差数列{an}的前n项和为Sn,等差数列{bn}的前n项和为Tn,若Sn/Tn=3n+1/5n-2,则a4/b4=? 设等差数列{an}的前n项和为Sn,等差数列{bn}的前n项和为Tn,若Sn/Tn=3n+1/5n-2,则a4/b4=? 等差数列an,bn的前n项和分别为Sn,Tn,若Sn/Tn=5n+1/3n-1,则a3/b3的值是多少. 等差数列an,bn的前n项和Sn,Tn满足Sn/Tn=3n+1/2n+5,则a3/b3= 已知Sn是无穷等差数列1,3,5...的前n项和,则limSn/S2n的值等于 已知等差数列an和bn的前n项和分别为Sn和Sn`,且Sn:Sn`=5n+2:3n+1,则a9：b9的值为? 设Sn是等差数列an的前n项和,若S3/S7=1/3,则S6/S7= 设Sn是等差数列An的前n项和,若S3/S6=1/3,则S6/S12等于 设Sn是等差数列an的前n项和,若S3/S6=1/3,则S6/S7=? 设Sn是等差数列{An}的前n项和,若S3/S6=1/3,则S6/S12=? 设Sn是等差数列的前n项和,S3:S6=1:3,则S6:S9=