Wu Chong-shi
a0a1a2a3 Γ
a4 a5 a61a7
a8a9a10a11 Γ
a12 a13
§12.1 Γ a14a15a16a17a18
a19a20 Γ
a21a22a23a24a25a26a27a28a29
Γ(z) =
integraldisplay ∞
0
e?ttz?1dt, Rez > 0.
a30a31a32a33a34a35a36a37a38 Eulera32a33a39a40a41
a23
a32a33a42a43 t
a44a45a46a47
a35 argt = 0
a48
star a49a50a51a52a53a54a55a56a57a58a59a60a61a62a63a48
a64a35a30
a29a65
a31a66
a25
a32a33a39a67a68
a29a65
a31a69a32a33(
a70t = 0a71)a39a72a29a65
a31a73a74a32a33a39a75a76a77a78a67a79
a80a81a82a33a83a33a84a85a86
a48 integraldisplay
∞
0
e?ttz?1dt =
integraldisplay 1
0
e?ttz?1dt +
integraldisplay ∞
1
e?ttz?1dt.
a87a88a36a37a82a33
a48
a89a90a39a91t ≥ 1
a92
a39a93a32
a21a22e
?ttz?1
a29 ta23a94a95a21a22
a39a96a97a98a35z
a23a21a22
a39
a70
a99a100a101
a47a102a48a103a27a46 4.2a104a105
a39a77a106a107a67a108a109
a65
a31
a47a102a21a22
a39a110a111a112a106a107a32a33
a65a113a114a115a48
a64a35
et =
∞summationdisplay
n=0
tn
n!,
a75a76a116a117a118a119a120a121
a22 N a39
et > t
N
N!, e
?t < N!
tN .
a122a116a117z a100a101a123a118
a65a124a125a126 (a127a125a126a128a23
a118a119
a65a129
a39a130a131 Rez<x
0
a39(
a132a133 12.1)
vextendsinglevextendsinglee?ttz?1vextendsinglevextendsingle < N!·tx
0?N?1.
a13412.1
a30a135a39a111a77a136a137a138a139a140
a23N ( a141a142N > x0)
a39a32a33
integraldisplay ∞
1
tx0?N?1dta110a114a115a39a122
integraldisplay ∞
1
e?ttz?1dta70za100
a101
a23
a118
a65a124a125a126
a41
a65a113a114a115
a39a64
a127a70
a99a100a101
a47a102a48
a77a106a107a36
a65
a82a33
a23
a32a33
a70a143a144
a100a101
a47a102
a39a145a146a147
a29
a106a107a67
a23a65a113a114a115a148a48
a64a35
vextendsinglevextendsinglee?ttz?1vextendsinglevextendsingle = e?ttx?1, x = Rez.
Wu Chong-shi
§12.1 Γa4a5a149a150a151 a62a7
a64
a127
a39a116a117z a100a101a123
a143a144
a100a101
a23
a118
a65a125a126
a39a131 Rez = x ≥ δ > 0a39
vextendsinglevextendsinglee?ttz?1vextendsinglevextendsingle ≤ tδ?1,
a152
integraldisplay 1
0
tδ?1dta114a115
a39a122a32a33
integraldisplay 1
0
e?ttz?1dta70z a100a101a123a143a144a100a101a23a118a65a124a125a126a41a65a113a114a115a39a64a127a70a143
a144
a100a101
a47a102a48
a78a81a82a33a153a154a83a39a110
a142a155
Γ(z) =
integraldisplay ∞
0
e?ttz?1dt
a70z a23a143a144
a100a101
a47a102a48 square
star a49a50a156a157a158a159a160
? a123a101a23
a32a33
a27a28
a41a39a32a33a161a162a96a163a112a77a164
a27a70a165a166
a123a39a152
a104a167a168
a35
Γ(z) =
integraldisplay
L
e?ttz?1dt, Rez > 0,
a32a33a161a162L
a29ta100a101a123a169t = 0a170a171a23a144a172a173
a39argt = αa35
a25a22
a39|α| <pi/2
a48
a174a175a176C
a177a13312.2a39a44a26a178a22a27a46
a85a86a179a42a32a33
contintegraldisplay
C
e?ttz?1dt,a110a180a106a142
a30a31
a181a86
a48
a13412.2
? a182a65a183a167a168a184
a32a33a161a162L
a104
a76
a29 t a100a101a123a169 t = 0 a170a171a23
a118a119a33a185a186a187a188
a173
a39a111a77
a24a189
a76
Ret → +∞a23a190a191a192
a117a73a74a193
a129a194a104a48
star a60a61a195a196
a197a198a199a200a201Γ
a202a203
a201a204a205a206a207a208a209Rez > 0
a48
a210a211a212a213a201a214
a215a216
a213a217a218a219a220a198a221a222a201a39
a223a224a39a225a226a227a228a229za201a219a220a198a39a206a230a208a207a231a201a232a233a234a212a213a214a235
a216
a213a227a228a229a219a220a198a236a237
a48
a238a239a240a241
a23a190a242a29a243a244a22a21a22
a98 Taylor
a245a246
integraldisplay 1
0
e?ttz?1dt =
∞summationdisplay
n=0
(?)n
n!
integraldisplay 1
0
tn+z?1dt =
∞summationdisplay
n=0
(?)n
n!
1
n + z.
a30a31a181a247
a29a70Rez > 0a23a248a249a250a142a155a23a48a251a252a191a253a71a70a143a144
a100a101
a47a102
a39a152
a143a71a23a254a22
a89a90
a70
a99a100
a101a123(z negationslash= 0,?1, ?2,···)
a65a113a114a115
a39a64a152
a70
a99a100a101
a47a102 (z negationslash= 0,?1,?2,···)a48
a30a255a107a39
a252a191a143a71a23a254
a22
a109a0
a191
a110
a29a253a71
a32a33a109a0
a191a70
a99a100a101a123
a23a47a102a1a2a48
Γ(z) =
integraldisplay ∞
1
e?ttz?1dt +
∞summationdisplay
n=0
(?)n
n!
1
n + z.
Wu Chong-shi
a0a1a2a3 Γ
a4 a5 a63a7
§12.2 Γ a14a15a16a3a4a5a6
a7a8 1 Γ(1) = 1
a48
a240a241
a70 Γa21a22a23a27a28
a41a108a9 z = 1
a194a104a142a155
a30a31a181a247
a48
a7a8 2 Γ(z + 1) = zΓ(z)
a48
a10 a11a12 Γ
a21a22a23a27a28
Γ(z + 1) =
integraldisplay ∞
0
e?ttzdt
= ?e?ttz
vextendsinglevextendsingle
vextendsingle
∞
0
+
integraldisplay ∞
0
e?tztz?1dt
= z
integraldisplay ∞
0
e?ttz?1dt = zΓ(z). square
a13a209a14a15a16a17a237a18a19a20a15a21a22a23a24a221
a48
? a235a217a25a26a218a27a28a29a30a31a208a229a226a32a33 Rez > 0a48
a34a35a209 Γ(z + 1)
a36zΓ(z)a37
a218a219a220a198a221
a222 (z = 0, ?1, ?2, ···
a38a39) a39a223a224a39a40a41a221a222a227a228a42a24a39a237a18a43a204a39a14a15a44a45a46a47a218
a219a220a198a48a49a50
a48
? a51
a235a232a198a39a52a237a18a53a54a55a29a44a45a46a47a23a56a49 Γ
a202a203
a201a221a222a227a228
a48
a14a57a39a237a234a44a45a46a47
a58a59a49
Γ(z) = 1zΓ(z + 1).
a197a60a61a62a201
a202a203
a218a63a220a198Rez > 0a197a221a222a39a64a62a201
a202a203
a218a63a220a198 Rez > ?1a197a221a222a65
a20a66a218a67a68a69a70 Rez > 0 a197a71a72
a65a35a224
a237a73
a39 Γ(z + 1)/z
a74
a217a64a62a201 Γ(z) a218a69a70
Rez > ?1a197a201a221a222a227a228a48a75a76
a39a77a17a78
a227a228a79a80a229a201a16a17a81a82a225 Γ(z)
a39a14
a74
a217a83a39
a237a18a78
Γ(z) = 1zΓ(z + 1), z negationslash= 0
a84
a49a217Γ(z)a218a69a70Rez > 1a197a201a204a205
a39
a75z = 0a85
a217Γ
a202a203
a201a235a86a87
a85
a39resΓ(0) = 1
a48
? a88a89
a197a90a91a92
a39a93
a237a18a234 Γ
a202a203
a227a228a229a69a70 Rez > ?2
a39
Γ(z) = 1z(z + 1)Γ(z + 2), z negationslash= 0,?1.
z = ?1a52a217Γa202a203
a201a235a86a87
a85
a39 resΓ(?1) = ?1
a48
? a77a224a94a95a39a74
a237a18a234 Γ
a202a203
a221a222
a227a228a229a219a220a198
a39
a75 z = 0, ?1, ?2, ···a37
a217Γ
a202a203
a201a235
a86a87
a85
a39
resΓ(?n) = (?1)
n
n! .
Wu Chong-shi
§12.2 Γa4a5a149a96a97a98a99 a64a7
a100a101 1 a116a117a120a121
a22 na39
Γ(n) = (n?1)!.
a120
a29
a64a35a30a31a102a64a39 Γ
a21a22
a72a34a35a103a104
a21a22a48
a7a8 3
a105a106a107
a43
a27a46
Γ(z)Γ(1?z) = pisinpiz.
a30a31a108
a191a23
a106a107
a132a189
a101
a23
a36 12.4
a109a48
a100a101 2 Γ(1/2) = √pi
a48
a111a77
a70
a123a101
a23a148a110 3 a41a108a9 z = 1/2 a39a96a97a111a119
Γ(1/2) >0(a64a35a93a32a21a22a112a113
a35a120)
a194a104a142a155a127
a181a247
a48
a100a101 3 Γ
a21a22a70
a99a100a101a73a114
a129a48
a10 a64a35pi/sinpiz negationslash= 0a39a75a76Γ(z)Γ(1?z) negationslash= 0
a48
a30
a135a39
a177
a247
a70 z = z0 a129
a131 Γ(z
0) = 0
a39a115a116a131 Γ(1?z
0) =
∞ a48a30a111a180a171a117a70 1 ? z0 = ?n(a118a194 z0 = n + 1)
a39
n = 0,1,2,···a92a48a251a127a92 Γ(z0) = Γ(n + 1) = n! a39a119a75
a120a121a122
a48
a64
a127 Γa21a22a70
a99a100a101a73a114
a129a48 square
a13312.3 a41a123a170a124Γ(x)(xa35a165a22)a23a133a125a48
a67a169
a165a22
a126a175a240a127a128a109a129
a170
a30a31a130a86a76a131 Γ
a21a22a23a132a129
a33a133
a48
a13412.3
a134
a135a136a137a138a139a140a141 Γ
a142
a139a143
a7a8 4
a144
a104a108
a191
Γ(2z) = 22z?1pi?1/2Γ(z)Γ
parenleftbigg
z + 12
parenrightbigg
.
a30a31a108
a191a23
a106a107a147
a132 12.4a109a48
a7a8 5 Γ
a21a22a23a145a146a245a246
a39
a194 Stirlinga108a191a184
a91|z|→∞a39|argz| <pi
a92
a39a131
Γ(z) ~ zz?1/2e?z√2pi
braceleftBig
1 + 112z + 1288z2 ? 13951840z3 ? 5712488320z4 +···
bracerightBig
,
lnΓ(z) ~
parenleftbigg
z ? 12
parenrightbigg
lnz ?z + 12 ln(2pi) + 112z ? 1360z3 + 11260z5 ? 11680z7 +···.
a70a147a46
a41a148
a25a26a23
a181a247
a29
lnn! ~ nlnn?n.
Wu Chong-shi
a0a1a2a3 Γ
a4 a5 a65a7
§12.3 ψ a14 a15
ψa21a22a29 Γa21a22a23
a116
a22a149a150
ψ(z) = dlnΓ(z)dz = Γ
prime(z)
Γ(z).
a11a12Γ
a21a22a23a148a110
a39
a104
a76
a142a170ψ(z)a23a250a151a148a110a184
1. z = 0,?1,?2,···a152a29ψ(z)a23a65
a103a153
a129
a39
a178a22
a130a35?1a65a154
a124
a30a155
a129
a76a156a39ψ(z)
a70
a99a100a101
a47a102a48
2. ψ(z + 1) =ψ(z) + 1z.
ψ(z + n) =ψ(z) + 1z + 1z + 1 +···+ 1z + n?1, n = 2,3,···.
3. ψ(1?z) =ψ(z) +picotpiz.
4. ψ(z)?ψ(?z) = ?1z ?picotpiz.
5. ψ(2z) = 12ψ(z) + 12ψ
parenleftbigg
z + 12
parenrightbigg
+ ln2.
6. ψ(z) ~ lnz ? 12z ? 112z2 + 1120z4 ? 1252z6 +···, z →∞, |argz| <pi.
7. limn→∞bracketleftbigψ(z + n)?lnnbracketrightbig = 0.
ψa21a22a23a157a158a112a131
ψ(1) = ?γ, ψprime(1) = pi
2
6 ,
ψ
parenleftbigg1
2
parenrightbigg
= ?γ ?2ln2, ψprime
parenleftbigg1
2
parenrightbigg
= pi
2
2 ,
ψ
parenleftbigg
?12
parenrightbigg
= ?γ ?2ln2 + 2, ψprime
parenleftbigg
?12
parenrightbigg
= pi
2
2 + 4,
ψ
parenleftbigg1
4
parenrightbigg
= ?γ ? pi2 ?3ln2, ψ
parenleftbigg3
4
parenrightbigg
= ?γ + pi2 ?3ln2,
ψ
parenleftbigg1
3
parenrightbigg
= ?γ ? pi2√3 ? 32 ln3, ψ
parenleftbigg2
3
parenrightbigg
= ?γ + pi2√3 ? 32 ln3.
a159a31γ = ?ψ(1)a217
a203a160
a31a201a235a15a161a162a163
a203
a39a164a225 Eulera163
a203
γ = 0.5772 1566 4901 5328 6060 6512 0900 8240 ···.
a165a201a204a205a217
γ = limn→∞
bracketleftBigg nsummationdisplay
k=1
1
k ?lnn
bracketrightBigg
.
star a166a26ψa21a22
a39
a104
a76
a190a167
a128a168
a170a169a170
a35a131
a46a191a23
a73a74
a254a22
∞summationdisplay
n=0
un =
∞summationdisplay
n=0
p(n)
d(n)
Wu Chong-shi
§12.3 ψ a4 a5 a66a7
a171a172a39a40a41p(n)a172d(n)
a152a29na23a173a170a191a48
a35
a124a174
a106
a254a22a114a115
a39 p(n)
a23a175a22a176a177
a77a238d(n)
a23a175a22
a1782a39
a194
limn→∞un = limn→∞n·un = 0.
a177
a247d(n)
a29na23ma175a173a170a191
a39a96a97a99a82a114
a129a152a29a65
a103a114
a129
a39
d(n) = (n + α1)(n + α2)···(n + αm),
a194un a111a131a65
a103a153
a129
a39a115
a104
a82a33a33
a191
a35
un = p(n)d(n) =
msummationdisplay
k=1
ak
n + αk.
a166a26ψa21a22a23a179
a130a145a180a39
a194a104
a168
a142
Nsummationdisplay
n=0
un =
msummationdisplay
k=1
ak [ψ(αk + N)?ψ(αk)]
=
msummationdisplay
k=1
ak [ψ(αk + N)?lnN ?ψ(αk)],
a40a41
a166a26a124
msummationtext
k=1
ak = 0a48a174a153a164N →∞a39a194a142
∞summationdisplay
n=0
un = lim
N→∞
msummationdisplay
k=1
ak [ψ(αk + N)?lnN ?ψ(αk)]
= lim
N→∞
msummationdisplay
k=1
ak [ψ(αk + N)?lnN]?
msummationdisplay
k=1
akψ(αk)
= ?
msummationdisplay
k=1
akψ(αk).
a181 12.1 a168a73a74
a254a22
∞summationtext
n=0
1
(3n + 1)(3n+ 2)(3n + 3)
a171a172
a48
a60
a64a35
1
(3n + 1)(3n + 2)(3n + 3) =
1
6
1
n + 1/3 ?
1
3
1
n + 2/3 +
1
6
1
n + 1,
a75a76a39a11a12a123a101a123
a170a23
a168a172a108
a191
a39a131
∞summationdisplay
n=0
1
(3n + 1)(3n + 2)(3n + 3) = ?
1
6
bracketleftbigg
ψ
parenleftbigg1
3
parenrightbigg
?2ψ
parenleftbigg2
3
parenrightbigg
+ψ(1)
bracketrightbigg
.
a108a9ψ
a21a22a23a157a158a112
a39
a194a142
∞summationdisplay
n=0
1
(3n + 1)(3n+ 2)(3n + 3) =
1
4
bracketleftbigg pi
√3 ?ln3
bracketrightbigg
.
a181 12.2 a168a73a74
a254a22
∞summationtext
n=0
1
n2 + a2
a171a172a39a40a41a > 0
a48
Wu Chong-shi
a0a1a2a3 Γ
a4 a5 a67a7
a60
a64a35
1
n2 + a2 =
i
2a
parenleftbigg 1
n + ia ?
1
n?ia
parenrightbigg
,
a75a76
∞summationdisplay
n=0
1
n2 + a2 = ?
i
2a [ψ(ia)?ψ(?ia)].
a166a26
a123a101
a151a170a23ψa21a22a23a148a110 4a39
ψ(ia)?ψ(?ia) = ? 1ia ?picotipia = i
bracketleftbigg1
a +pi coth pia
bracketrightbigg
,
a110
a104
a76a168
a142
∞summationdisplay
n=0
1
n2 + a2 =
1
2a2
bracketleftbig1 +piacothpiabracketrightbig.
star a177a247un
a182
a131a37a103a153
a129
a39a183
a177
a39
d(n) = (n + α1)(n + α2)···(n + αm)(n + β1)2(n + β2)2···(n + βl)2,
a115
un = p(n)d(n) =
msummationdisplay
k=1
ak
n + αk +
lsummationdisplay
k=1
bracketleftbigg b
1k
n + βk +
b2k
(n + βk)2
bracketrightbigg
.
a184
a44
a128a39
a254a22a114a115a23a248a249a29
msummationdisplay
k=1
ak +
lsummationdisplay
k=1
b1k = 0.
a11a12ψ
a21a22a23a179
a130a145a180a39
a194a142
∞summationdisplay
n=0
un = ?
msummationdisplay
k=1
akψ(αk)?
lsummationdisplay
k=1
bracketleftbigb
1kψ(βk)?b2kψprime(βk)
bracketrightbig.
a181 12.3 a168a73a74
a254a22
∞summationtext
n=0
1
(n + 1)2(2n + 1)2
a171a172
a48
a60
a64a35
1
(n + 1)2(2n + 1)2 =
bracketleftbigg 4
n + 1 +
1
(n + 1)2
bracketrightbigg
?
bracketleftbigg 4
n + 1/2 ?
1
(n + 1/2)2
bracketrightbigg
,
a75a76
∞summationdisplay
n=0
1
(n + 1)2(2n + 1)2 = ?
bracketleftbig4ψ(1)?ψprime(1)bracketrightbig+bracketleftbigg4ψparenleftbigg1
2
parenrightbigg
+ψprime
parenleftbigg1
2
parenrightbiggbracketrightbigg
= 2pi
2
3 ?8ln2.
Wu Chong-shi
§12.4 B a4 a5 a68a7
§12.4 B a14 a15
Ba21a22a29a103
a36
a65
a38 Eulera32a33
a27a28a23a184
B(p,q) =
integraldisplay 1
0
tp?1(1?t)q?1dt, Rep > 0, Req > 0.
a185t = sin2θ a39
a182
a104
a76
a142a155 Ba21a22a23a186a65
a31a109a0
a191
B(p,q) = 2
integraldisplay pi/2
0
sin2p?1θcos2q?1θdθ.
a70Ba21a22a23a27a28
a41a98a42a187 s = 1?ta39a110
a104
a76
a142a155
B(p,q) =
integraldisplay 1
0
tp?1(1?t)q?1dt
=
integraldisplay 0
1
(1?s)p?1sq?1 (?ds)
=
integraldisplay 1
0
sq?1(1?s)p?1 ds,
a194B(p,q)a116a117pa172q a29
a116a34
a23a184
B(p,q) = B(q,p).
Ba21a22a104
a76
a26 Γa21a22
a109a188
a170
a83a39
B(p,q) = Γ(p)Γ(q)Γ(p + q) .
a10
a70Rep > 0a39Req > 0a23a248a249a250
a39a89a90a131
Γ(p) =
integraldisplay ∞
0
e?ttp?1dt = 2
integraldisplay ∞
0
e?x2x2p?1dx,
Γ(q) =2
integraldisplay ∞
0
e?y2y2q?1dy.
a117
a29
Γ(p)Γ(q) = 4
integraldisplay ∞
0
integraldisplay ∞
0
e?(x2+y2)x2p?1y2q?1dxdy.
a185x = rsinθ a39y = rcosθ a39
a142
Γ(p)Γ(q) =4
integraldisplay ∞
0
integraldisplay pi/2
0
e?r2(rsinθ)2p?1(rcosθ)2q?1rdrdθ
=4
integraldisplay ∞
0
e?r2r2(p+q)?1dr
integraldisplay pi/2
0
sin2p?1θcos2q?1θdθ
=Γ(p + q)B(p,q). square
a189a208a14a15a46a47a60a39a237a78 B
a202a203
a221a222
a227a228a229 p
a36q a201a219a220a198a48
a19a14a15a46a47a60
a39
a52a237a18a190a191a192
a84a193B(p,q)a13a209p
a36q a217a13a164a201a48
Wu Chong-shi
a0a1a2a3 Γ
a4 a5 a69a7
a129
a70
a11a12 B
a21a22
a172Γ
a21a22a23
a145a180
a191
B(p,q) = Γ(p)Γ(q)Γ(p + q) . (star)
a194a106Γ
a21a22a23
a81a31
a148a110
a39
a194a105a106a107
a43
a27a46
Γ(z)Γ(1?z) = pisinpiz
a172
a144
a104a108
a191
Γ(2z) = 22z?1pi?1/2Γ(z)Γ
parenleftbigg
z + 12
parenrightbigg
.
a87a106a107
a105a106a107
a43
a27a46
a39
a70 (star)a191
a41a185p = z, q = 1?z a39
B(z, 1?z) = Γ(z)Γ(1?z)Γ(1) = Γ(z)Γ(1?z).
a186a65a190
a101a39
B(z, 1?z) =
integraldisplay 1
0
tz?1(1?t)?zdt.
a185x = t/(1?t)a39a123
a191a194a104a195
a35
B(z, 1?z) =
integraldisplay ∞
0
xz?1
1 + xdx.
a30a31a32a33
a70
a36 7.6
a109
a41a196a197a198a199a200a39a30a135a110a106
a142
Γ(z)Γ(1?z) = B(z, 1?z) = pisinpiz.
a30a31a106a107a91a90
a29a700 < Rez < 1a23a248a249a250a142a155a23a48a251a29
a39
a103
a117
a252a191a23
a81
a71a70
a99a100a101
a152a47a102
a39a64
a127
a39
a30a31
a252a191a70
a99a100a101a130a80a201
a48 square
a202a106a107
a144
a104a108
a191a48
a30
a104
a76
a169
a200a32a33
integraldisplay 1
?1
(1?x2)z?1dx, Rez > 0
a23
a198a199
a142a155a48
a185 x2 = ta39a115
a142integraldisplay
1
?1
(1?x2)z?1dx = 2
integraldisplay 1
0
(1?x2)z?1dx =
integraldisplay 1
0
(1?t)z?1t?1/2dt
= B
parenleftbigg
z, 12
parenrightbigg
= Γ(z)Γ(1/2)Γ(z + 1/2) .
a203a98a42a187 1 + x = 2ta391?x = 2(1?t)a39a115a131
a186a65a204a125a191a23
a181a247
a184integraldisplay
1
?1
(1?x2)z?1dx = 22z?1
integraldisplay 1
0
tz?1(1?t)z?1dt = 22z?1B(z, z) = 22z?1Γ(z)Γ(z)Γ(2z) .
a117
a29
Γ(z)Γ(1/2)
Γ(z + 1/2) = 2
2z?1Γ(z)Γ(z)
Γ(2z) a194a144
a104a108
a191 Γ(2z) = 22z?1pi?1/2Γ(z)Γ
parenleftbigg
z + 12
parenrightbigg
.
a30a205
a23
a106a107a206a90
a29a70Rez > 0 a23a248a249a250a182a207a23a48a251a29
a39a120
a177a208
a101
a173a175
a86a106a200
a23
a39a30a31a181a247
a70
a99a100a101
a152
a80a201
a48 square
Wu Chong-shi
?§12.5 Γ
a4a5a149a209a210a211a212a213 a610a7
?§12.5 Γ
a14a15a16a214a215a216a217a218
Γa21a22a23a27a28 (a36a37a38a219a220a32a33)
Γ(z) =
integraldisplay ∞
0
e?ttz?1dt, Rez > 0.
a111a221
a26
a117
a143a144
a100a101
a48
a35
a124a222
a194a30
a65a223a224
a39a225
a109
a163a226a106a107a128a227a228 Γ
a21a22a23a186
a156a229
a204
a109a0
a191
a39
a190a191a230
a231a175a176a32a33a109a188a172a73a74a104a32a109a188a39a67a232
a152a70
a99a100a101a80a201 (
a233
a155
a129a104
a180a183a156)
a48
a131a145a106a107
a132a234a235a236a237
[12]a39a363a238a48
1. Γa62a63a158a239a240a49a50a57a241
Γ(z) = ? 12isinpiz
integraldisplay (0+)
∞
e?t(?t)z?1dt, |arg(?t)| <pi,
a40a41
a23
a32a33a175a176a35
a184
a169a123
a144
a100a101a242
a146
a120
a165a166
a73a74a193a243
a170a171
a39
a253a207a244
a102
a129
a120a245
a65a246
a39a202
a143a207a155a250a144
a100a101a242
a146
a120
a165a166
a73a74a193a243 (
a132a133 12.4)a48a127a191a70
a99z a100a101a80a201a39
a251 z =a121a22
a154a156
a48
a134 12.4 a134 12.5
Γa21a22a23a186a65
a31a175a176a32a33a109a188
a29
Γ(z) = 12pii
integraldisplay (0+)
?∞
ett?zdt, |argt| <pi,
a32a33a175a176a169
a250a144
a100a101a242
a146a247a165a166
a73a74a193a243
a170a171
a39
a143a207a244
a102
a129
a120a245
a65a246
a39a202
a253a207a155
a123
a144
a100a101a242
a146a247
a165a166
a73a74a193a243 (
a132a133 12.5)a48a127a191a70
a99z a100a101a80a201a39
a230
a231 z =a121
a22a48
2. Γa62a63a158a248a249a250a251a252a49a57a241
Γ(z) = 1z
∞productdisplay
n=1
braceleftbiggparenleftBig
1 + zn
parenrightBig?1 parenleftbigg
1 + 1n
parenrightbiggzbracerightbigg
,
a127a191
a116a118a253 z a130a80a201a39
a251
a153
a129 z =a247
a121
a22
a154a156
a48
3. Γa62a63a158a254a255a0a1a249a0a250a251a252a49a57a241
1
Γ(z) = ze
γz
∞productdisplay
n=1
bracketleftBigparenleftBig
1 + zn
parenrightBig
e?z/n
bracketrightBig
,
a40a41
γ = limn→∞
bracketleftBigg nsummationdisplay
k=1
1
k ?lnn
bracketrightBigg
= 0.5772156649···
a110
a29
a219a220
a25a22 (12.3a109)a48
a30a31a73a74a104a32a123
a170a124
a118a253 z
a23 Γ(z)a39a2a92a244
a107
a124 Γ(z)a23a132a129
a35
a65
a103a153
a129z = 0,?1,?2,···
a152a73a114
a129a48
Wu Chong-shi
a0a1a2a3 Γ
a4 a5 a611a7
a169Γ
a21a22a23
a73a74a104a32a109a188
a104a142a155a65
a180
a151
a131a119
a28a23
a181a247
a48
a183
a177
sinpiz = piΓ(z)Γ(1?z) =piz
∞productdisplay
m=1
bracketleftbigg
1? z
2
m2
bracketrightbigg
,
cospiz = sin2piz2sinpiz =
∞productdisplay
m=1
bracketleftbigg
1? 4z
2
(2m?1)2
bracketrightbigg
.
a243
a30a81
a191
a168a116
a22a149a150
a39a72
a104
a76
a142a155
pitanpiz = ?8z
∞summationdisplay
m=1
1
4z2 ?(2m?1)2, z negationslash= ±
1
2,±
3
2,···, (App1)
picotpiz = 1z + 2z
∞summationdisplay
m=1
1
z2 ?m2, z negationslash= 0,±1,±2,···, (App2)
picscpiz =pi2
bracketleftBig
tanpiz2 + cotpiz2
bracketrightBig
= 1z + 2z
∞summationdisplay
m=1
(?1)m
z2 ?m2, z negationslash= 0,±1,±2,···, (App3)
pisecpiz =picscpi
parenleftbigg1
2 ?z
parenrightbigg
= 4
∞summationdisplay
m=1
(?1)m(2m?1)
4z2 ?(2m?1)2, z negationslash= ±
1
2,±
3
2,···. (App4)
a30a155
a245a246a191
a34a35a131
a46
a33
a191a245a246a48
a30
a204a245a246a23a125a191
a163a2a117a3a232a200a4
a132
a200
a23 Taylora245a246
a172 Laurent
a245
a246
a65
a114a115
a126a175
a152a29
a99a100a101 (
a132a129
a243a154a156) a39a147a163
a29a233a65a5a126a6a7a126a48a70
a30
a204a245a246
a41a39a180a78
a21a22a70
a67
a23
a99a82a153
a129a23a132a8a148
a2
a92
a109a129a73a9
a48
a180a139a98a131
a46
a33
a191a245a246a23
a39a10a164a117
a70
a131a164
a125a126a128
a111a131a153
a129a23a11
a112a12a13a14a15a16a17a12a13a18
a19(8.1)
a20(8.2)a21a22a23a24a25a26a14a27a28a29a30a31a32a33a34
pi2sec2piz =4
∞summationdisplay
m=?∞
1
[2z ?(2m?1)]2, z negationslash= ±
1
2,±
3
2,···,
pi2csc2piz =
∞summationdisplay
m=?∞
1
(z ?m)2, z negationslash= 0,±1,±2,···.
a19(App1)~(App4)
a35a22a36a37a38z = 0a39a40Taylora41a42a14a43a44a45a24a20a46a47a14a48a28a29a33a34
piz tanpiz = 2
∞summationdisplay
n=1
bracketleftbigg ∞summationdisplay
m=1
1
(2m?1)2n
bracketrightbigg
(2z)2n, (App5)
piz cotpiz = 1?2
∞summationdisplay
n=1
bracketleftbigg ∞summationdisplay
m=1
1
m2n
bracketrightbigg
z2n, (App6)
pisecpiz = 4
∞summationdisplay
n=0
bracketleftbigg ∞summationdisplay
m=1
(?)m?1
(2m?1)2n+1
bracketrightbigg
(2z)2n, (App7)
pizcscpiz = 1 + 2
∞summationdisplay
n=1
bracketleftbigg ∞summationdisplay
m=1
(?)m?1
m2n
bracketrightbigg
z2n. (App8)
a49
a31a50a51a14
z
2 cot
z
2 =
iz
2
eiz/2 + e?iz/2
eiz/2 ?e?iz/2 =
∞summationdisplay
n=0
(?)n B2n(2n)!z2n, |z| < 2pi;
Wu Chong-shi
?§12.5 Γ
a52a53a54a55a56a57a58a59 a6012a61
z
2 tan
z
2 =
z
2 cot
z
2 ?z cotz =
∞summationdisplay
n=1
(?)n?12
2n ?1
(2n)! B2nz
2n, |z| <pi;
z cscz = z2 cot z2 + z2 tan z2 =
∞summationdisplay
n=0
(?)n?12
parenleftbig22n?1 ?1parenrightbig
(2n)! B2nz
2n, |z| <pi;
2ez/2
ez + 1 = sech
z
2 =
∞summationdisplay
n=0
En
n!
parenleftBigz
2
parenrightBign
, |z| <pi,
a62a63 B
n a20 En a64a65a66a67
Bernoulli a13a20 Euler a13 (a68a69 5.6 a70a14a71a72a73a74
a67a75a76
) a14a20a77a51a78
(App5)~(App8)a22a79a80a81a14a48a28a29a33a82a83a84a85a86a87a13a20a88
∞summationdisplay
m=1
1
m2n =
(?)n?1
2
(2pi)2n
(2n)! B2n,
∞summationdisplay
m=1
(?1)m?1
m2n = (?)
n?122n?1 ?1
(2n)! pi
2nB2n,
∞summationdisplay
m=1
1
(2m?1)2n =
(?)n?1
2
22n ?1
(2n)! pi
2nB2n,
∞summationdisplay
m=1
(?1)m?1
(2m?1)2n+1 =
(?)n
22n+2
pi2n+1
(2n)! E2n.
a19
a77a51a78a89a31a22a90a91a92
B2n = (?)n?1 2(2n)!(2pi)2n
∞summationdisplay
m=1
1
m2n,
a93
a28a29a94a82a95 n →∞a96B2n →∞a18a97a98a14
B20 = ?5.291×102, B30 = 6.016×108, B40 = ?1.930×1016,
B50 = 7.501×1024, ··· B200 = ?3.647×10215.