数列{an}前n项和Sn=n^2+n 1.求{an}通项 2.若bn=(1/2)^an+n,求{bn}前n项和Tn
数列{an}前n项和Sn=n^2+n 1.求{an}通项 2.若bn=(1/2)^an+n,求{bn}前n项和Tn
数列{an},a1=1,an=2-2Sn,求an,若bn=n*an,求{bn}的前n项和Tn
设bn=(an+1/an)^2求数列bn的前n项和Tn
已知数列{an}前n项和Sn=n^2+n,令bn=1/anan+1,求数列{bn}的前n项和Tn
an=3*2^(n-1),设bn=n/an求数列bn的前n项和Tn
数列an,满足Sn=n^2+2n+1,设bn=an*2^n,求bn的前n项和Tn
已知数列{an}的前n项和Sn=2^n-1,若bn=n.求数列{anbn}的前n项和Tn
等差数列{an}、{bn}的前n项和分别为Sn、Tn,若Sn/Tn=2n/3n+1,求an/bn
两个等差数列{an},{bn}的前n项和分别为Sn,Tn,若Sn/Tn=2n/3n+1,求an/bn.
等差数列{an},{bn}的前n项和分别为Sn,Tn,若Sn/Tn=2n/3n+1,求an/bn的表达式
an=2*3^n-1 若数列bn满足bn=an+(-1)^n*ln(an),求数列bn前n项和Sn
数列an的前n项和为Sn,Sn=2an-1,数列bn满足b1=2,bn+1=an+bn.求数列bn的前n项和Tn