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1.已知数列{an}满足Sn=2n^2-3n,求an
2.已知{an}满足a1=0,a(n+1)=n^2+2n-Sn,(n为正整数),求an
3.已知等差数列{an}的公差是正数,a3a7=-12,a4a6=-4,求公差d
4.已知{an}满足9Sn=10an+9(n+10),求an
5.在各项都是正数的等比数列{an}中,若公比q不为1,且a3,a5,a6成等差数列,则公比q为_______
6在等比数列{an}中,a1,a10是方程2x^2+4x+1=0的两个根,那么a4a7=__________
7在等比数列{an}中,an<0,a2a4+2(a3a5)+a4a6=25,a3+a5=__________
8.若Sn和Tn分别表示数列{an}和{bn}的前N项和,an=-(2n+3)/2,4Tn-12Sn=13n,求bn
9.已知数列{an}满足a1=1,a(n+1)=n*an/(n+1),求an
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