{bn}为等差数列,bn=(2n^2-n)/(n+c),求非0常数c

{bn}为等差数列,bn=(2n^2-n)/(n+c),求非0常数c 已知数列{bn}前n项和为Sn,且2(Sn-n)=n*bn,求证{bn}是等差数列. 等差数列{an},{bn}的前n项和分别为An,Bn,切An/Bn=2n/3n+1,求lim(n→∞)an/bn 等差数列{an} {bn}前n项和为An Bn,An/Bn=(7n+2)/(4n+27),求an/bn 等差数列{an} {bn}前n项和为An Bn,An/Bn=(7n+2)/(4n+27),求an/bn 计算等差数列{an}{bn}的前n项和分别为An.Bn,且An/Bn=2n/(n+1)求limn→∞(an/bn) 已知{an},{bn}均为等差数列,前n项的和为An,Bn,且An/Bn=2n/(3n+1),求a10/b10的值 等差数列{An},{bn}的前n项和为An,Bn,且An/Bn=n/3n-2,则a5/b5=? 已知等差数列{an}和{bn},他们的前n项之和为An和Bn,若An/Bn=(5n+3)/(2n-1)A9/B9 等差数列{an}的前n项和为An,等差数列{bn}的前n项和为Bn若Bn/An=n/3n+1 1.求a5/b5 2 an/bn bn=1/(2n-1)(2n+1),数列bn的前n项和为Bn,求证,Bn 数列{an}{bn}满足bn=a1+2a2+3a3+…+nan/(1+2+3+…+n),若数列{an}为等差数列,求证；{bn}为等差数列. 已知（an）为等差数列 求证（bn)=3n+2为等差数列 两个数列{an}和{bn}满足bn=a1+2a2+...+nan/1+2+...+n,求证：若{bn}为等差数列,则数列{an}也是等差数列?能看懂的 {an}和{bn}满足bn=(a1+2a2+.+nan)/(1+2+.+n) 求证：（1）若{bn}为等差数列,{an}也是等差数列 已知数列an是等差数列 且bn=2^a｛n｝求证bn为等比数列 ｛｝里为下标 ^为上标 an,（bn)^2,a(n+1)成等差数列,（bn）^2,a(n+1),(b(n+1))^2成等比数列,证：（bn）为等差数列 等差数列bn=(a1+a2+3a….an)/n(1)bn=n^2,求｛an｝(2){bn}为等差数列,求证｛an｝也为等差数列错了 是 （a1+a2-+a3...+an）/n