设A1=2,An+1=2/（1+An）,求An通项..求详解,感激不尽..谢...

设数列{an}中,a1=2,an+1=an+n+1,则通项an=? 设a1,a2,...,an都是正数,证明不等式(a1+a2+...+an)[1/(a1)+1/(a2)+...+1/(an)]>=n^2 设数列,a1=3,an+1=3an-2,求数列an是等比数列 设数列【an】满足a1=1,3（a1+a2+a3+······+an）=（n+2）an,求通项an 关于数列、等差数列的题目设数列an满足an+1=an-2且a1=241）判断an是什么数列2）若an 设数列{an},a1=2,a（n+1）=an+In·（1+1/n）,求an 设A1=2,An+1=2/（1+An）,求An通项..求详解,感激不尽..谢... 设数列AN满足A1等于1,3(A1+a2+~+AN)=(n+2)an,求通向公式 设数列{an}满足a1=1, an=(4an-1 +2)/(2an-1 +7) ,则通项xn=? 数列{An}满足a1=1/2,a1+a2+..+an=n方an,求an 设数列{an}满足a1=1a2=2an=1/3（an-1+2an-2）求an题目为设数列{an}满足a1=1，a2=2，an=1/3（an-1+2an-2）求an 数列{an}满足a1=3/2,an+1=an2-an+1,求证：1/an=1/(an)-1 - 1/(an+1)-1数列{an}满足a1=3/2,an+1=an2-an+1,求证：1/an=1/(an)-1 - 1/(an+1)-1设Sn=1/a1+1/a2+...+1/an,n>2证明1 数列an中,a1=3,an+1=an/2an+1,则an=? 设{an}为等比数列,q>0(1)lim（a1+a2+...+an）/（a6+a7+...+an）(2)lim（a1+a2+...+an）/(a1^2+a2^2+...+an^2) 设{an}是a1=4的单调递增数列,且满足an+1^2+an^2+16=8（an+1+an）+2an+1an,求ann+1均为a的下标 设b＞0,数列an满足a1=b,an=nban-1/an-1+n-1（n≥2）求数列an通向公式. 设b＞0,数列an满足a1=b,an=nban-1/an-1+n-1（n≥2）求数列an通向公式 数列 (10 18:35:56)设数列{an}满足a1=9,an+1=-1/2an+3,求an的通项公式（含过程）