设等差数列{an}满足a3=5,a10=-9,Sn是数列{an}的前n项和,则Sn的最大值为______.
设等差数列{an}满足a3=5,a10=-9,Sn是数列{an}的前n项和,则Sn的最大值为______.
设等差数列(An)的前n项和为Sn,已知A3=24,S11=0.求数列(An)的通项公式和Sn的最大值.
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成等差数列
设数列{an}的前n项和为Sn满足2Sn=an+1-2n+1+1,n∈N*,且a1,a2+5,a3成等差数列.
设Sn是等差数列{an}的前n项和,若a4=9,S3=15,则数列{an}的通项为______.
设等差数列【An】满足A3=5,A10=-9,求通项公式,前n的和Sn及最大的序号n的值
一道数学题:设数列An是公差不为0的等差数列.前n项和是Sn,满足(a2)^2+(a3)^2=(a4)^2+(a5)^2
已知数列an是等差数列 其中a2=22 a7=7,设an的前n项和为Sn,求Sn的最大值
等差数列{an}中,a3=-5,a6=1,此数列的通项公式为______,设Sn是数列{an}的前n项和,则S8等于__
设数列an的前n项和为Sn,已知S1=1,Sn+1/Sn=n+c/n,且a1,a2,a3成等差数列
设数列an的前n项和为Sn,满足2Sn=an-2∧n+1 +1 ,且a1,a2+5,a3成等差
已知数列{an}的前n项和为Sn,且满足an+2Sn*Sn-1=0,a1=1/2.求证:{1/Sn}是等差数列