已知数列an满足an=(an-1)-(an-2)(n≥3,n∈N)它的前n项和为Sn,若S13=1,则a1=?

已知数列{an}满足a1=1 an+1=an/(3an+1) 则球an 已知数列{an}满足a(n+1)=an+n,a1=1,则an= 已知数列{an}满足a(n+1)=an+lg2,a1=1,求an 已知数列an满足1/a-an=2根号n,且an>0.求an的通项公式是数列{an}满足1/an-an=2根号n，且an>0，求an的通项公式。 已知数列an满足a1=1,a(n+1)=an/(3an+2),则an=? 已知数列an满足条件a1=-2 a（n+1）=2an/(1-an) 则an= 周期性数列问题i已知数列｛an}满足a(n+1)=2an (0 已知数列{an}中满足(An+1-An)(An+1+An)=16,且a1=1,an 已知数列{an}满足an+1=an+n,a1等于1,则an=? 已知数列{an}满足an+1=2an+3.5^n,a1=6.求an 已知数列an满足a1=1,a(n+1)=an/(3an+1) 求数列通项公式 已知数列｛An｝满足a1=1,a（n+1）=2an+1 求证数列{an+1}是等比数列 求数列｛an｝通式 数列题,求通项已知数列｛An}满足A=2An/(1-An),A1=2,求数列｛An}的通项公式 已知数列{an}满足,a1=2,a(n+1)=3根号an,求通项an数列{an}满足:an>0,且根号下Sn=an+1/4,求通项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（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=1/2,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=1,1/an+1=根号1/an^2+2,an>0,求an 已知数列{an}满足a1=1,a2=3,an+2=3an+1-2an求an