an+1-√3=(an+3/an+1)-√3=……=(1-√3)*(an-√3)/(an+1) 又bn=an-√3绝对值,所以得bn+1=(1-√3)/【(an)+1】的绝对值*bn ∵an=1,可推导出an>=1恒成立,进一步推导得,bn+1