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(1)

.a 8 , +Q``2+iBQM

o2M/`2/B kk /û+2K#`2 kyRd GǶmb;2 /2b +H+mHi`B+2b MǶ2bi Tb miQ`Bbû

1t2`+B+2 ,

GǶTT`BiBQM /2b i2`K2bp+q 7Bi T2Mb2` ¨ bQKK2` 2M /B;QMH2X

G bû`B2 2bi ¨ i2`K2b TQbBiB7b /QM+ KāK2 Mim`2 [m2 H bû`B2 /2b bQKK2b 2M /B;QMH2bX SQm`n}tû-Sn=P

p+q=nap,q=Pn p=0

1 n+ 1

1

2n = 1 (n+ 1)2n

Pn

p=01 = 1 2nX S` i?ûQ`ĕK2 /2 bQKKiBQM 2M /B;QMH2- QM HQ`bP

p

P

qap,q=P

nSn=P

n

1

2n = 1

1 1/2 = 2T`

bû`B2 ;ûQKûi`B[m2 /2 `BbQM1/2X

1t2`+B+2 ,

RX aQBi">0X S` BMiû;`iBQM T` T`iB2b UH2b 7QM+iBQMb bQMiC1bm`[",1]-R1

"

arctant

t dt= [ln(t) arctan(t)]1"

R1

"

lnt 1 +t2dt.

GQ`b[m2" i2M/ p2`b y-ln(t") arctan(") ⇠"ln(") !0X .QM+ H2 +`Q+?2i ;ûMû`HBbû 2bi +QMp2`;2Mi U/2 HBKBi2 MmHH2V 2i H2b BMiû;`H2b ;ûMû`HBbû2bR1

0

arctant

t dt2iR1 0

lnt

1 +t2dtQMi KāK2 Mim`2- /QM+

+QMp2`;2Mi2b +`R1 0

arctant

t dt2bi 7mbb2K2Mi BKT`QT`2 2M y U+`arctan(t)⇠0t)X PM Q#iB2Mi #B2M H 7Q`KmH2 /2KM/û2X

kX SQm` iQmit2]0,1[- QM t22]0,1[2i /QM+ T` .a1- 1

1 +t2 =P+1

n=0( 1)n 1t2nX BMbB- lnt 1 +t2 = P+1

k=0( 1)n 1t2nlnt=P fn(t)X

G2b 7QM+iBQMbfnBMbB /û}MB2b bQMi +QMiBMm2b T` KQ`+2mt 2i H bû`B2P

fn+QMp2`;2 bBKTH2K2Mi bm`

]0,1[X 1M}M-R1

0|fn|= 1

(2n+ 1)2 [mB 2bi H2 i2`K2 ;ûMû`H /ǶmM2 bû`B2 +QMp2`;2Mi2 T` +QKT`BbQM p2+ H bû`B2 ¨ i2`K2b TQbBiB7bP 1

4n2 +QMp2`;2Mi2 T` +`Biĕ`2 /2b bû`B2b /2 _B2KMM U2>1VX 6BMH2K2Mi- T` i?ûQ`ĕK2 /ǶBMiû;`iBQM i2`K2 ¨ i2`K2 /2 "2TTQ@G2pB- QM Q#iB2Mi H 7Q`KmH2 /2@

KM/û2 ,

Z1 0

arctant t dt=

+1X

n=0

( 1)n (2n+ 1)2 jX PM T2mi `2i`Qmp2` +2 `ûbmHii 2M /K2iiMi [m2

8t2R,arctan(t) =

+1X

n=0

( 1)n 2n+ 1t2n+1. 2i 2M TTHB[mMi ¨ MQmp2m H2 i?ûQ`ĕK2 /ǶBMiû;`iBQM i2`K2 ¨ i2`K2X

(2)

S`Q#HĕK2 , miQm` /2 H 7QM+iBQM x2i Hi2`Mû2 /2 _B2KMM

AX :ûMû`HBiûb RX aQBix 2 Rc bBx > 0- HQ`b H bmBi2Å

1 nx

ã

n 1

2bi /û+`QBbbMi2 URV p2`b y UkV c /ǶT`ĕb H2 +`Biĕ`2 bTû+BH /2b bû`B2b Hi2`Mû2b- H bû`B2 P

n 1

( 1)n 1

nx +QMp2`;2 c bBx0- H bmBi2 Å

( 1)n 1 nx

ã

n 1

M2 +QMp2`;2 Tb p2`b y- /QM+ H bû`B2 P

n 1

( 1)n 1

nx /Bp2`;2 U;`QbbBĕ`2K2MiVX kX *QKK2| t|<1- H bû`B2 ;ûQKûi`B[m2P

( t)n+QMp2`;2 2i b bQKK2 pmi+1P

k=0

( t)k= 1 1 ( t) = 1

1 +tc /QM+ H bmBi2(gn)+QMp2`;2 bBKTH2K2Mi p2`b H 7QM+iBQMg:t7! 1

1 +t bm`[0,1[X

• G bmBi2(gn)+QMp2`;2 bBKTH2K2Mi p2`b H 7QM+iBQMgbm`[0,1[c

• H 7QM+iBQMg2i H2b 7QM+iBQMbgn, n2NbQMi +QMiBMm2b UT` KQ`+2mtV c

+QM/BiBQM /2 /QKBMiBQM,8t2[0,1[, |gn(t)|= 1 ( t)n+1

1 +t = 1 ( t)n+1 1 +t  2

1 +t = (t)c H 7QM+iBQM 2bi BM/ûT2M/Mi2 /2n- +QMiBMm2 UKāK2 bm`[0,1]V 2i BMiû;`#H2 bm`[0,1[X .ǶT`ĕb H2 i?ûQ`ĕK2 /2 +QMp2`;2M+2 /QKBMû2- H bmBi2

ÇZ 1 0

gn

å

+QMp2`;2 p2`bZ1 0

gX P`-Z1

0

gn= Xn

k=0

( 1)k k+ 1 =

n+1X

k=1

( 1)k 1

k c /QM+F(1) = Z 1

0

g=h

ln(1 +t)i1 0= ln 2X jX 8n 1,8x 2, ( 1)n 1

nx  1

n2X *QKK2 H bû`B2 P

n 1

1

n2 2bi BM/ûT2M/Mi2 /2n2i +QMp2`;2Mi2- H bû`B2 P

n 1

( 1)n 1

nx +QMp2`;2 MQ`KH2K2Mi bm`[2,+1[X .QM+ bQM `2bi2Rn(x) = P

n N+1

1

nx i2M/ p2`b y 2i TQm`N bb2x ;`M/|RN|"/2X 9X S` BHH2m`b-|F(x) 1| PN

n=2

1 nx + P

n N+1

1

nxX GQ`b[m2xi2M/ p2`b+1- H bQKK2 U}MB2V PN

n=2

1 nx i2M/ p2`b y T` QTû`iBQMb bm` H2b HBKBi2b +` 1

nx !0TQm` n 2X AH 2tBbi2 /QM+A >0 i2H [m2 TQm` iQmix > A- PN

n=2

1 nx "/2

6BMH2K2Mi- TQm`x > A-|F(x) 1|"/QM+F i2M/ p2`b R HQ`b[m2xi2M/ p2`b+1X 8X GB2M p2+

SQm`x >1- F(x) ⇣(x) = +1P

n=1

( 1)n 1 1 nx = +1P

k=1

2

(2k)x = 21 x+1P

k=1

1

kx = 21 x⇣(x).PM 2M

/û/mBi HǶû;HBiû ,F(x) = (1 21 x)⇣(x).

eX *QKK221 x !

x!+1 0-F(x)⇠⇣(x)m pQBbBM;2 /2+12i /QM+⇣(x) !

x!+1 1X dX .û`Bp#BHBiû /2F

X aQBix >0X G 7QM+iBQMhx:t7!lnt

tx 2bi /2 +Hbb2C1 bm`]0,+1[2ih0x(t) = tx 1(1 xlnt) t2x X .QM+h0x2bi Mû;iBp2 bm` HǶBMi2`pHH2[21/x,+1[2i TQbBiBp2 bm`]0,21/x]X .QM+hx2bi /û+`QBbbMi2 bm`[21/x,+1[2i +`QBbbMi2 bm`]0,21/x]X

PM 2M /û/mBi [m2 H bmBi2Å lnn

nx ã

n 1

2bi /û+`QBbbMi2 ¨ T`iB` /m `M;b21/xc+ 1 [mB 2bi mM 2MiB2` bmTû`B2m` Qm û;H ¨ 21/xX

e

(3)

#X fn:x7!( 1)n 12 xlnn2bi /2 +Hbb2C12ifn0(x) = ( 1)nlnn nx X aQBia >0X PM TQb2Na =b21/ac+ 1X SQm` iQmi x a- H bmBi2Å

lnn nx

ã

n Na

i2M/ p2`b y 2M /û+`QBbbMi c /QM+ H bû`B2 Hi2`Mû2 P

n Na

fn0(x) +QMp2`;2 2i- TQm`n Na- bQM `2bi2 /ǶQ`/`2n-

n(x)- pû`B}2 ,

|⇢n(x)| ( 1)n+1ln(n+ 1)

(n+ 1)x ln(n+ 1) (n+ 1)a. .QM+ sup

x a|⇢n(x)|  ln(n+ 1)

(n+ 1)a n!+1! 0X .QM+ H bû`B2 P

n 1

fn0 +QMp2`;2 mMB7Q`KûK2Mi bm`

[a,+1[X

• SQm` iQmin 1- H 7QM+iBQMfn2bi /2 +Hbb2C1bm`]0,+1[c

• H bû`B2 P

n 1

fn+QMp2`;2 bBKTH2K2Mi bm`]0,+1[2i b bQKK2 2biFc

• H bû`B2 P

n 1

fn0 +QMp2`;2 mMB7Q`KûK2Mi bm` iQmi b2;K2Mi BM+Hmb /Mb]0,+1[X .ǶT`ĕb H2 i?ûQ`ĕK2 /2 /û`BpiBQM i2`K2 ¨ i2`K2-F 2bi /2 +Hbb2C1bm`]0,+1[2i

8x >0, F0(x) =

+1X

n=1

( 1)nlnn nx .

AAX S`Q/mBi /2 *m+?v /2 H bû`B2 Hi2`Mû2 T` 2HH2@KāK2 3X úim/2 /2 H +QMp2`;2M+2

X GQ`b[m2x >1- H bû`B2 P

n 1

( 1)n 1

nx +QMp2`;2 #bQHmK2Mi c /ǶT`ĕb H2 i?ûQ`ĕK2 /m T`Q/mBi /2

*m+?v UQm bQKK2 2M /B;QMH2bV- H bû`B2 T`Q/mBi /2 P

n 1

( 1)n 1

nx T` 2HH2@KāK2 +QMp2`;2

#bQHmK2Mi 2i b bQKK2 pmi ,Å+1 P

n=1

( 1)n 1 nx

ã2

= (F(x))2X

#X SQm` x > 0- cn(x) = ( 1)n 2nP1

k=1

1

[k(n k)]xX *QKK2 k 7! k(n k) 2bi KtBKmK [mM/

k= n

2 2i [m2 H bQKK2 +QKTQ`i2n 1i2`K2b-|cn(x)|=nP1

k=1

1

[k(n k)]x (n 1) 1 [(n/2)2]x = (n 1)4x

n2x X SQm` 0 < x  1

2- (n 1)4x

n2x mM2 HBKBi2 bi`B+i2K2Mi TQbBiBp2 U}MB2 Qm MQMV- /QM+ H bmBi2 (cn(x))M2 +QMp2`;2 Tb p2`b yX .QM+ H bû`B2 P

n 2

cn(x)/Bp2`;2 ;`QbbBĕ`2K2MiX NX *b Qɍx= 1

X 1

[X] (n [X]) = 1 n

Å 1

[X]+ 1 n [X]

ãX .QM+

cn(1) = ( 1)n 2

n 1

X

k=1

1

k(n k) = ( 1)n 21 n

nX1 k=1

Å1 k + 1

n k

ã

= ( 1)n 21 n

n 1

X

k=1

1 k+

n 1

X

k=1

1 n k

!

= 2( 1)n 21 n

nX1 k=1

1

k = 2( 1)n 2Hn 1

n .

(4)

#X JQMQiQMB2 Hn 1

n

Hn

n+ 1 = 1 n

Å Hn 1

n

ã Hn

n+ 1=Hn

Å1 n

1 n+ 1

ã 1 n2 Å

1 +1 2

ã 1 n(n+ 1)

1

n2 = n 2 2n2(n+ 1) 0.

.QM+ H bmBi2Å Hn 1

n ã

n 2

2bi /û+`QBbbMi2X

+X S` +QKT`BbQM bû`B2bfBMiû;`H2b p2+ H 7QM+iBQMt7!1/t- QM T2mi ûi#HB` H2 `ûbmHii +HbbB[m2 , Hn⇠lnnm pQBbBM;2 /2+1X .QM+ H bmBi2ÅHn 1

n ã

n 2

+QMp2`;2 p2`b y 2M /û+`QBbbMi 2i H bû`B2 Hi2`Mû2 P

n 2

cn(1)+QMp2`;2X

AAAX *H+mH /2 H bQKK2 /ǶmM2 bû`B2 ¨ HǶB/2 /ǶmM2 ûim/2 /2m pQBbBM;2 /21 RyX .ûp2HQTT2K2Mi bvKTiQiB[m2 2M R

X PM TQb2h=x 1X *QKK2F 2bi /û`Bp#H2 2M R- m pQBbBM;2 /21- QM , F(x) =F(1) +hF0(1) +o(h) = ln 2 +hF0(1) +o(h).

PM mbbB ,1 21 x= 1 2 hln 2=hln 2 ln22

2 h2+o(h2)m pQBbBM;2 /2x= 1X

#X .ûp2HQTT2K2Mi /2

⇣(x) = F(x)

1 21 x = ln 2 +hF0(1) +o(h) hln 2 ln22

2 h2+o(h2)

= 1

hln 2

ln 2 +hF0(1) +o(h) 1 ln 2

2 h+o(h)

= 1

hln 2(ln 2 +hF0(1) +o(h)) Å

1 +ln 2

2 h+o(h) ã

= 1

hln 2 Ç

ln 2 +h Ç

F0(1) +ln22 2

å +o(h)

å

= 1

h+ ÅF0(1)

ln 2 +ln 2 2

ã +o(1) RRX .ûp2HQTT2K2Mi bvKTiQiB[m2 2M R U#BbV

X SQm`n 12ix2[1,2]-t7! 1

tx 2bi /û+`QBbbMi2 bm`[n, n+ 1]U[mB 2bi mM BMi2`pHH2 /2 HQM;m2m`

RV- /QM+1. 1 (n+ 1)x

Z n+1 n

/t tx 1. 1

nxX PM 2M /û/mBi [m2 ,0vn(x) 1 nx

1 (n+ 1)x.

#X SQm` x 2 [1,2]- H bmBi2 Å 1 nx

ã

n 1

+QMp2`;2 Up2`b yV c +QKK2 Pn

k=1

Å 1 kx

1 (k+ 1)x

ã

= 1 1

(n+ 1)x- H bû`B2 P

n 1

Å 1 nx

1 (n+ 1)x

ã+QMp2`;2X .2 HǶ2M+/`2K2Mi /m UV- QM /û/mBi H +QMp2`@

;2M+2 /2 H bû`B2 P

n 1

vn(x)X +X SQm`x2]1,2]- Pn

k=1

vk(x) = Pn

k=1

1 kx

Z n+1 1

/t

tx n!+1!⇣(x) Z +1

1

/t

tx =⇣(x) 1 x 1X /X G bû`B2 P

n 1

vn +QMp2`;2 bBKTH2K2Mi bm`[1,2]X PM MQi2 Rn(x) = +1P

k=n+1

vk(x)H2 `2bi2 /ǶQ`/`2 n/2 H bû`B2X .ǶT`ĕb UV-0Rn(x) +1P

k=n+1

Å 1 kx

1 (k+ 1)x

ã

= 1

(n+ 1)x limk!+1 1 kx = 1

(n+ 1)xX .QM+ sup

x2[1,2]|Rn(x)| 1

(n+ 1)1 n!+1!0X .QM+ H bû`B2 P

n 1

vn +QMp2`;2 mMB7Q`Kû@

K2Mi bm`[1,2]X

3

(5)

2X SQm`x2]1,2]-vn(x) = 1 nx

1 1 x

Å 1 nx 1

1 (n+ 1)x 1

ãcvn(1) = 1

n ln(n+ 1) + lnnX vn 2bi +QMiBMm2- bm7 T2mi@āi`2 2M RX

1M R , 2M TQbMih=x 1- 1 nx = 1

n+o(1)T` +QMiBMmBiû /2 HǶ2tTQM2MiB2HH2x7!n x 2M R 2i 1

1 x Å 1

nx 1

1 (n+ 1)x 1

ã

= 1

h 2 hlnn 2 hln(n+1) = 1 h

⇣(1 hlnn+o(h)) (1 hln(n+

1) +o(h)⌘

= ln(n+ 1) lnn+o(1)c /QM+ vn(x) = 1

n+ ln(n+ 1) lnn+o(1)X .QM+vn2bi +QMiBMm2 2M RX

PM 2M /û/mBi [m2 H bû`B2 P

n 1

vn2bi mM2 bû`B2 /2 7QM+iBQMb +QMiBMm2b bm`[1,2]X G +QMp2`;2M+2 mMB7Q`K2 bm`[1,2]2Mi`ŗM2 /QM+ H +QMiBMmBiû /2 b bQKK2 bm`[1,2]X

PM 2M /û/mBi [m2⇣(x) 1

x 1 =+1P

n=1

vn(x) = Å+1

P

n=1

vn(1) ã

+o(1) = +o(1)m pQBbBM;2 /2 1+X .ǶQɍ⇣(x) = 1

x 1+ +o(1)m pQBbBM;2 /21+X RkX TTHB+iBQM

S` mMB+Biû /m /ûp2HQTT2K2Mi HBKBiû 2M1+Uûp2Mim2HH2K2Mi 2M KmHiBTHBMi T`(x 1)V- QM /û/mBi /2 3XU#V 2i NXU2V H2b û;HBiûba= 12i F0(1)

ln 2 +ln 2

2 =b= X .ǶQɍF0(1) = ln 2

Å ln 2 2

ãX

.ǶT`ĕbAX9XU#V-+1P

n=1

( 1)n 1lnn

n = F0(1) = ln 2 Åln 2

2 ãX

AoX *H+mH /2 ⇣(4)2i TTHB+iBQM ¨ H T?vbB[m2 , SQm`x >1- QM TQb2⇣(x) =X

n 1

1

nxX PM `TT2HH2 U2i QM /K2iV [m2⇣(2) =X

n 1

1 n2 =⇡2

6 . SQm`m2N2in2N- QM TQb2 , (m, n) = 2

mn3+ 1 m2n2+ 2

m3nX

RjX X aQBi X

m 1

X

n 1

(m, n) X

m 1

X

n 1

(m, n+m) X

m 1

X

n 1

(m+n, n).

.ǶmM2 T`i- QM T2mi pû`B}2` [m2 (m, n) (m, n+m) (m+n, n) = 2 m2n2X HQ`b

X

m 1

X

n 1

(m, n) X

m 1

X

n 1

(m, n+m) X

m 1

X

n 1

(m+n, n) = X

m 1,n 1

2 m2n2

= X

m 1

ÑX

n 1

2 m2n2

é

=X

m 1

2 m2

ÑX

n 1

1 n2

é

= 2 ÑX

n 1

1 n2

é ÑX

m 1

1 m2

é

= 2⇣(2)2. S` BHH2m`b ,

G T`2KBĕ`2 bû`B2 +Q``2bTQM/ ¨ H bQKK2 /2 iQmb H2b i2`K2b (a, b)TQm`(a, b)2(N)2UTHM bmTû`B2m` /`QBiVX

G b2+QM/2 bû`B2 +Q``2bTQM/ ¨ H bQKK2 /2b i2`K2b (a, b)i2Hb [m2(a < b)bBimûb bi`B+i2K2Mi m /2bbmb /2 H /B;QMH2 /m [m`i /2 THMX

G i`QBbBĕK2 bû`B2 +Q``2bTQM/ ¨ H bQKK2 /2b i2`K2b (a, b)i2Hb [m2(a > b)bBimûb bi`B+i2K2Mi 2M /2bbQmb /2 H /B;QMH2 /m [m`i /2 THMX

6BMH2K2Mi- HǶ2Mb2K#H2 +Q``2bTQM/ ¨ H bQKK2 /2b i2`K2b (a, b)i2Hb [m2a=bUH /B;QMH2 /m THMV- +Ƕ2bi ¨ /B`2P

a2N (a, a) =P

n 1

5

a4 = 5·⇣(4)X

(6)

#X .QM+5⇣(4) = 2⇣(2)2= 2⇡4

36 2i QM T2mi HQ`b 2M /û/mB`2 [m2

⇣(4) =X

n 1

1 n4 =⇡4

90.

R9X .ûi2`KBM2`- T`ĕb pQB` DmbiB}û bQM 2tBbi2M+2- 2i 2M /ûiBHHMi H2b +H+mHb HǶBMiû;`H2Z +1 0

t3 2t 1dt SQm`t >0- +QKK20exp( t)<1- QM t3

et 1=t3e t 1

1 e t =t3P

n2Ne (n+1)t=P fn(t)X

*?[m2fn2bi +QMiBMm2 bm`]0,+1[- TQbBiBp2b 2i BMiû;`#H2 +` 7mbb2K2Mi BKT`QT`2 2M y 2io(1/t2) 2M+1X G bû`B2 /2 7QM+iBQM +QMp2`;2 bBKTH2K2Mi p2`bf [mB 2bi +QMiBMm2 2i BMiû;`#H2X

SQm`n2N-Z

|fn|= 1 (n+ 1)4

Z +1 0

u3exp( u) du2M TQbMiu= (n+1)t+?M;2K2Mi /2 p`B#H2b

#BD2+iB7X

S` ASS Qm 2M `2+QMMBbbMi H 7QM+iBQM - QM }MH2K2Mi Z

|fn| = 6

(n+ 1)4 [mB 2bi H2 i2`K2

;ûMû`H /ǶmM bû`B2 +QMp2`;2Mi2 T` +`Biĕ`2 /2 _B2KMMX .QM+ T` BMiû;`iBQM i2`K2 ¨ i2`K2 /2 "2TTQ@G2pB-Z

f=X

n 0

6

(n+ 1)4= 6⇣(4) = ⇡4 15X R8X aQBiM = c

4 Z +1

0

8⇡hc

5

1

exp(kBhcT) 1d X PM TQb2t='( ) = hc

kB T +?M;2K2Mi /2 p`B#H2b #BD2+iB7X HQ`b = hc

kBtT 2id = hc kBt2T dt 1iM =

Z 0 +1

2⇡hc2kB5t5T5 h5c5

( hc) kBt2T

1

exp(t) 1dt= Z +1

0

2⇡hc2kB5t5T5 h5c5

hc kBt2T

1 exp(t) 1dt T`ĕb bBKTHB}+iBQMb 2i /ǶT`ĕb HǶBMiû;`H2 +H+mHû2 H [m2biBQM T`û+û/2Mi2-

...= 2⇡kB4T4 h3c2

4 15= T4 p2+ = 2⇡5k4B

15h3c2X

Ry

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