记Sn=a1+a2/2+a3/3+a4/4……+an/n=An+B,则a1=S1=A+B,当n>=2时,an/n=Sn-S(下标n-1)=An+B-[A(n-1)+B]=A,an=An,所以,an={A+B,n=1;An,n>=2.当B=0时,an=An,a(下标n+1)=A(n+1),a(下标n+1)-an=A,{an}是等差数列,当B≠0时,a1...