数列an满足an+1 - an + an-1=0 (n≥2),且a1=1,a2=-1,则a2011= a.1 b.-1
已知数列an满足an=1+2+...+n,且1/a1+1/a2+...+1/an
已知数列an中 a1=3 a2=6 an+2=an+1-an(n+1 和n加2 是下标) 则a2011=
数列{an}满足a1=3/2,an+1=an^2-an+1,则1/a1+1/a2+...+1/a2010+1/a2011
已知数列{an}满足:a1=1,且an-a(n-1)=2n.求a2,a3,a4.求数列{an}通项an
一直数列{An}满足A1=1/2,A1+A2+…+An=n^2An
数列{an}满足a1=1,且an=an-1+3n-2,求an
已知数列an满足an=1+2+...n,且(1/a1)+(1/a2)+...(1/an)
已知数列{an}满足:a1=1,且an-an-1=2n,求(1)a2,a3,a4.(2)求数列{an}的通项an
关于数列极限的已知数列an满足a1=0 a2=1 an=(an-1+an-2)/2 求lim(n->无穷)an
设数列an满足a1=a2=1,a3=2,且对正整数n都有an·an+1·an+2·an+3=an+an+1+an+2+a
设数列{an}满足a1=0,且a(n+1)=an+1/4+(根号(1+4an))/2 1.求a2
【高中数学数列】已知数列an满足a1=1,a2=2,且an=an-1/an-2 (n大于等于3)则a2012=?