在等比數(shù)列{an}中,a1=1,公比為q,且|q|≠1.若am=a1a2a3a4a5,則m=__________.

數(shù)列{an}的前n項(xiàng)和為Sn,已知Sn=1-2+3-4+…+(-1)n-1·n,則S17=__________.

(2014·重慶模擬)已知等差數(shù)列{an}滿足a2+a4=4,a3+a5=10,則它的前6項(xiàng)的和S6=________.

已知數(shù)列{2n-1·an}的前n項(xiàng)和Sn=9+2n,則數(shù)列{an}的通項(xiàng)公式為an=________.

已知函數(shù)f(x)對(duì)應(yīng)關(guān)系如表所示,數(shù)列{an}滿足a1=3,an+1=f(an),則a2015=________.

數(shù)列{an}的前n項(xiàng)和記為Sn,a1=t,點(diǎn)(Sn,an+1)在直線y=2x+1上,n∈N*,若數(shù)列{an}是等比數(shù)列,則實(shí)數(shù)t=______.

已知函數(shù)f(x)=2x,等差數(shù)列{an}的公差為2,若f(a2+a4+a6+a8+a10)=4,則log2[f(a1)·f(a2)·f(a3)·…·f(a10)]=________.

設(shè){an}是公比為正數(shù)的等比數(shù)列,a1=2,a3=a2+4.

(1)求{an}的通項(xiàng)公式.

(2)設(shè){bn}是首項(xiàng)為1,公差為2的等差數(shù)列,求{an+bn}的前n項(xiàng)和Sn.

已知數(shù)列{an}滿足an+1=(n∈N*),且a1=.

(1)求證：數(shù)列是等差數(shù)列,并求an.

(2)令bn=(n∈N*),求數(shù)列{bn}的前n項(xiàng)和Tn.

已知數(shù)列{an}為等差數(shù)列,a3=5,a7=13,數(shù)列{bn}的前n項(xiàng)和為Sn,且有Sn=2bn-1,

(1)求{an},{bn}的通項(xiàng)公式.

(2)若cn=anbn,{cn}的前n項(xiàng)和為Tn,求Tn.