搜索
_-91.2.3.411.2.1.2.3.4.5.6.7.41.y=x2.,3.4.11.2.n1.nnn2.3.nnn1an12??nnana1a2a3??an??{an}1a,-3,-1,1,b,5,7,9;(2)20102{an}nn12345?1?an=nnnn+an={an}annan=f(n)an=(-1)=?n111123451nn+n?-1,n=2k-1(kz)+1,n=2k?11.41.411.414??3123456456789n+f(n)n1f(1),f(2),f(3),??f(n)??anf(n)an=2n+1.41123456?(2)10,9,8,7,6,5,?(3)1,0,1,0,1,0,?(4)a,a,a,a,a,?(n=1)?s15{an}nsnanan=?s-s(n2)n-1?n{an}nsn=2n+3{an}141211357??22-132-142-152-12234511113--1*22*33*44*549999999999?57777777777?(6)8,88,888,8888?n2+n-12{an}an=(nn+)31a1,a2a3an+1an227923320031415._____4.1475.10.a40b45c50d552133462d2an-an-1=d(n2)an+1-an=d(n1)an=2n-1an-an-1=an=a1+(n-1)dapd0d=0d0a121.{an}a7+a9=16a4=1a15b30c31d642.{an}a1=1d=3an=2005na667b668c669d6703.an=2n-1,bn=-2n+1anbnaabaaba=a+b2aab?a=a+b22an+1=an+an+22an=an-m+an+m106i{an}a1+a2+a3=15a1a2a3=80a11+a21+31a=a120b105c90d752.{an}1248a1b.2c.4d.81{an}22{an}3{aan}mnnm+an=am+(n-m)dd=an-n-m(mn)4{an}mnpqn+m+n=p+qam+an=ap+aqnsn(a1+an)n=2=nan(n-1)11+2d=2n2+ad1-2n(s2n=an+bn(a,b)?{an})s(a1+an)n(am+an-(n=2=m-1))n21.{an}a3+a4+a5=12a1+a2+...+a7=a14b21c28d352.2009sn{an}na2=3a6=11s7()a13b35c49d633.2009{an}nsns9=72,a2+a4+a934.20102{an}a1+a9=10a5a5b6c8d105.3343146390a.13b.12c.11d.106.{an}nsns12=21a2+a5+a8+a11=7.2009{an}nsna5=5a3898bnb1=1b1+b2+?+b10=100.bnbn9.{an}a10=1010s10=70d()s9=s5a-23112b-c.d.33310.2009{an}nsn,a6=s3=12,an=snn1100ansnanns77s1575tnntn12.{an}nsna10=30a20=50ansn=242n13.{an}1s8=48,s12=168,a1d2a6=10,s5=5,a8s8(3)a3+a15=40,s17.412ns-s=ndsa=nsan+1sn=sn-122n-1s-s=an=a.sn,s2n-sn,s3n-s2n1.{an}m302m1003ma.130b.170c.210d.2602.n482n603n3{an}10100100101104.sn{an}ns4=14s10-s7=30s9506iisnanns31s6s63s12da113bc381019an+1-an=d(nn*?{an}2an+1=an+an+2nn*)?{an}an=kn+b(k,b)?{an}(a,b)?{an}nsn=an2+bn1.{an}an-an-1=2{an}a.b.c.d.2.{an}an=2n+5{an}a.b.c.d.3.{an}nsn=2n+4{an}a.b.c.d.4.{an}nsn=2n{an}a.b.c.d.5.{an}an+2-2an+1+an=0{an}a.b.c.d.522()20165101113-51contor2122x-x-703x-3x+2=045y=x2672x+y=18121910y=221x11xxy+y-2y2122031245679101238112cantor18451918412nn*(n+)zqr:aa_____________________aa_________________?22x-10a5_______a,-3_______a32x-y+1=0b(-1,4)_______b,(1,3)_______b,-2_______b5aa1222az,bz)a10232m1xx-xx:1x,x,x,x2,-x3ppa2b3c4d52aby=abab++|a||b||ab|a.3b.3,2,1c.31-1d.3-1:--aaa1aa.1-a12aa.2aaa.3.aa+2(a+1)2a+3a+311aa21?aa?2