a1=15 3a(n+1)=3an-2 数列中相邻2项乘积是负数的项是第几和第几项?

在数列{an}中,a1=15,3a(n+1)=3an-2,n属于N*,若an 数列{an},a1=3,an*a(n+1)=(1/2)^n,求an 已知数列｛an｝中,a(n+1)=an+2^n,a1=3,求an 已知a1=2 a(n+1)=2an+2^n+3^n 求an 2an+a(n-1)=3,a1=2 a(n+1)=2an/3an+4,a1=1/4,求an 数列[An]满足a1=2,a（n+1）=3an-2 求an 在数列{an}中.a1=3且a(n+1)=an^2,求an a(n+1)=an-2*3(n次方)+1,a1=3,求an 已知A1=2,An=3A（n-1）+2n ,求通项公式 an a1=2,a（n+1）（角标）=an+3n,求an an中,a1=2,a(n+1)=3an+3(n+1)次方-2n次方,求an 写出下列数列{an}的前5项 a1=1,a(n+1)=an+3 a1=2,a(n+1)=2an a1=3,a2=6,a(n+2)=a(n+1)-an 数列{An}满足A1=1,A(n+3)=An+3,A（n+2)=An +2 在数列｛an｝中,a1=3,a(n+1)=an+n,求an 已知a1=3,a(n+1)=(3n-1)/(3n+2)an(n≥1),求an 数列｛an},a1=1,an+1=2an-n^2+3n,求｛an｝. (1)数列{an}中,a1=1,a2=-3,a(n+1)=an+a(n+2),则a2005=____(2)已知数列｛an｝满足a1=1,a1×a2×a3…an=n^2,求an.