递推法求通项如an+1 -an=3^n,求an通项哦打错了.是an+1 -3an=3^n

递推法求通项如an+1 -an=3^n,求an通项哦打错了.是an+1 -3an=3^n 数列｛an},a1=1,an+1=2an-n^2+3n,求｛an｝. 已知数列{an}中,a1=1,an+1=3an/(an+3)(N∈N*),求通项an, a1=1,an+1=an/(3+an),求an=?（n为下标） an+1 ,n+1是下表 ,an+1=an^3 a1=2 ,求an 数列｛an｝满足a1=1,且an=an-1+3n-2,求an 在数列an中,a1=2 an+1=an+3n则an= 已知{an}满足a1=1.an=3*n+2An-1,求an 在数列{an}中,a1=1,a2=5,an+2=an+1-an (n∈N*), 则a100等于an+2=an+1-an,an+3=an+2-an+1, 两式相加可得an在数列{an}中,a1=1,a2=5,an+2=an+1-an (n∈N*), 则a100等于( )方法一: an+2=an+1-an,an+3=an+2-an+1, 两式相加 数列{an}中,a1=2,an+1=4an-3n+1,求证{an-n}是等比数列 4an中n为下标an+1中n+1为下标an-n中an的n为下标 数列{an}中,a1=3,an-an*an+1=1(n∈N*),An表示数列{an}的前n项之积,则A2009 An+1=3XAn+2n+1 怎么算出An+1-An=3(An-An-1)+2 在｛an｝中,a1=1,an+1=3an+2n,试求｛an｝的通项an An={n （1 数列an满足a1=1/3,Sn=n(2n-1)an,求an 数列{an},a1=3,an*a(n+1)=(1/2)^n,求an a1=1,an+1=an+3^n-n,求an与sn 在数列｛an｝中,a1=3,a(n+1)=an+n,求an