若数列{an}满足1/an+1-1/an=d(n为正整数d为常数),则称数列{an}为调和数列,已知数列{1/x}为调和数列,且x1+x2+…+x20=200则x3+x18=

已知数列{an}满足a1=1 an+1=an/(3an+1) 则球an 若数列an满足a1=1,且an+1=an/1+an.证明:数列1/an为等差数列,并求出数列an的通项公 设数列{an}满足an=2an-1+n 若{an}是等差数列,求{an}通项公式 若数列{an}满足条件log2(1+an)=n,求数列{an}通项公式an= 若数列an满足a1=0.5 an+1=an/5an+1 则an=?an+1为an的后一项 数列{an}满足a1=a,an+1=1+1/an.若3/2 已知数列{an}中满足(An+1-An)(An+1+An)=16,且a1=1,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 数列{an}满足a1=1 an+1=2n+1an/an+2n 已知数列{an}满足an+1=an+n,a1等于1,则an=? 数列｛an｝满足a1=1,且an=an-1+3n-2,求an 数列an满足a1=2,an+1=4an+9,则an=? 已知数列{an}满足an+1=2an+3.5^n,a1=6.求an 数列{An}满足a1=1/2,a1+a2+..+an=n方an,求an 数列an满足a1=2,an+1=an²求an 数列an满足a1=2,an+1=an²求an 数列[An]满足An+1-An+3=0,且A1=-5.求An. 数列{an}满足an=p/(pn+1-p)(0