1.求an"2,f(a1),f(a2).f(an),2n+4,...成等差数列"从2到2n+4共n+2项,因此（2n+4）-2=（n-1）d,其中d为公差,得d=2.所以f(an)=2n+22.求Snf(an)=2n+2以及“f(x)=LOGaX(a>0且a不等于1)”得an=a^(2n+2)=a^2*(a^2)*n,即公比...