已知:等差数列,满足an+an+1+an+2=4则该数列为递增数列求证明n+1,n+2是下标

已知等差数列{an}满足an+1=an²-nan+1,则an=______. 已知数列an满足 a1=1/2,an+1=3an/an+3求证1/an为等差数列已知数列an满足 a1=1/2,an+1=3an/an+3求证1/an为等差数列 已知数列{An}满足A1=1,An+1=2An+2^n.求证数列An/2是等差数列 已知数列[an]满足An+1=1+an /3-an ,且a1=1/3,求证数列[1/(an -1）]是等差数列,并求an 已知数列｛an｝满足2an/an+2=an+1(n属于正整数）,a1=1/1006.求证：数列｛1/an｝是等差数列,并求通项an 已知数列{an}满足a1=2,an+1=2an/an+2.求证数列{1/an}是否为等差数列 并求出an 已知等差数列{an}中,a1=2.an+1=an+3分之an 求an 已知数列{an}满足an+1=(3an+1)/(an+3),a1=-1/3 求证1/(an)+1为等差数列,求an题目错了……重发已知数列{an}满足an+1=(an-1)/(an+3)，a1=-1/3 求证1/(an)+1为等差数列，求an 满足an+1-an=an-an-1 可以证明是等差数列么? 已知数列{an},{bn}满足a1=2,2an=1+2an*an+1,设{bn}=an-1求数列{1n}为等差数列急！！！ 已知an满足a1=三分之二 an+1=an-2/2an-3 求证1/an-1是等差数列如题 已知数列an满足an+1=3an/an+3求证{1/an}是等差数列.当a1=1/2时求a100 已知数列an满足:an+1-2an=2^n+1,且a1=2 (1)证明{an/2^n}是等差数列 (2)求数列an的 已知数列an满足a1=3,An+1=2An+2^n (1)求证数列[An/2^n]是等差数列 (2)求an通项公式 已知等差数列〔an〕满足a1=1,an+1 已知等差数列{an}满足a(n+1)=an+3n+2,且a1=2,求an.雪地跪拜! 已知数列{an}满足2an/an+2=an+1(n属于正整数),a1=1/1006.求证:数列{1/an}是等差数列,并求通项an已知数列{an}满足（2an）/（an+2）=a（n+1）(n属于正整数),a1=1/1006.求证:数列{1/an}是等差数列,并求通项an， 已知数列{an}满足a1=1 an+1=an/(3an+1) 则球an