Database
BASIC REAL AND COMPLEX FUNCTIONS
Basic number theory
Quadratic residues and the Legendre symbol
lgsval2lem
Next ⟩
lgsval4lem
Metamath Proof Explorer
Ascii
Unicode
Theorem
lgsval2lem
Description:
Lemma for
lgsval2
.
(Contributed by
Mario Carneiro
, 4-Feb-2015)
Ref
Expression
Hypothesis
lgsval.1
⊢
F
=
n
∈
ℕ
⟼
if
n
∈
ℙ
if
n
=
2
if
2
∥
A
0
if
A
mod
8
∈
1
7
1
−
1
A
n
−
1
2
+
1
mod
n
−
1
n
pCnt
N
1
Assertion
lgsval2lem
⊢
A
∈
ℤ
∧
N
∈
ℙ
→
A
/
L
N
=
if
N
=
2
if
2
∥
A
0
if
A
mod
8
∈
1
7
1
−
1
A
N
−
1
2
+
1
mod
N
−
1
Proof
Step
Hyp
Ref
Expression
1
lgsval.1
⊢
F
=
n
∈
ℕ
⟼
if
n
∈
ℙ
if
n
=
2
if
2
∥
A
0
if
A
mod
8
∈
1
7
1
−
1
A
n
−
1
2
+
1
mod
n
−
1
n
pCnt
N
1
2
prmz
⊢
N
∈
ℙ
→
N
∈
ℤ
3
1
lgsval
⊢
A
∈
ℤ
∧
N
∈
ℤ
→
A
/
L
N
=
if
N
=
0
if
A
2
=
1
1
0
if
N
<
0
∧
A
<
0
−
1
1
seq
1
×
F
N
4
2
3
sylan2
⊢
A
∈
ℤ
∧
N
∈
ℙ
→
A
/
L
N
=
if
N
=
0
if
A
2
=
1
1
0
if
N
<
0
∧
A
<
0
−
1
1
seq
1
×
F
N
5
prmnn
⊢
N
∈
ℙ
→
N
∈
ℕ
6
5
adantl
⊢
A
∈
ℤ
∧
N
∈
ℙ
→
N
∈
ℕ
7
6
nnne0d
⊢
A
∈
ℤ
∧
N
∈
ℙ
→
N
≠
0
8
7
neneqd
⊢
A
∈
ℤ
∧
N
∈
ℙ
→
¬
N
=
0
9
8
iffalsed
⊢
A
∈
ℤ
∧
N
∈
ℙ
→
if
N
=
0
if
A
2
=
1
1
0
if
N
<
0
∧
A
<
0
−
1
1
seq
1
×
F
N
=
if
N
<
0
∧
A
<
0
−
1
1
seq
1
×
F
N
10
6
nnnn0d
⊢
A
∈
ℤ
∧
N
∈
ℙ
→
N
∈
ℕ
0
11
10
nn0ge0d
⊢
A
∈
ℤ
∧
N
∈
ℙ
→
0
≤
N
12
0re
⊢
0
∈
ℝ
13
6
nnred
⊢
A
∈
ℤ
∧
N
∈
ℙ
→
N
∈
ℝ
14
lenlt
⊢
0
∈
ℝ
∧
N
∈
ℝ
→
0
≤
N
↔
¬
N
<
0
15
12
13
14
sylancr
⊢
A
∈
ℤ
∧
N
∈
ℙ
→
0
≤
N
↔
¬
N
<
0
16
11
15
mpbid
⊢
A
∈
ℤ
∧
N
∈
ℙ
→
¬
N
<
0
17
16
intnanrd
⊢
A
∈
ℤ
∧
N
∈
ℙ
→
¬
N
<
0
∧
A
<
0
18
17
iffalsed
⊢
A
∈
ℤ
∧
N
∈
ℙ
→
if
N
<
0
∧
A
<
0
−
1
1
=
1
19
13
11
absidd
⊢
A
∈
ℤ
∧
N
∈
ℙ
→
N
=
N
20
19
fveq2d
⊢
A
∈
ℤ
∧
N
∈
ℙ
→
seq
1
×
F
N
=
seq
1
×
F
N
21
1z
⊢
1
∈
ℤ
22
prmuz2
⊢
N
∈
ℙ
→
N
∈
ℤ
≥
2
23
22
adantl
⊢
A
∈
ℤ
∧
N
∈
ℙ
→
N
∈
ℤ
≥
2
24
df-2
⊢
2
=
1
+
1
25
24
fveq2i
⊢
ℤ
≥
2
=
ℤ
≥
1
+
1
26
23
25
eleqtrdi
⊢
A
∈
ℤ
∧
N
∈
ℙ
→
N
∈
ℤ
≥
1
+
1
27
seqm1
⊢
1
∈
ℤ
∧
N
∈
ℤ
≥
1
+
1
→
seq
1
×
F
N
=
seq
1
×
F
N
−
1
F
N
28
21
26
27
sylancr
⊢
A
∈
ℤ
∧
N
∈
ℙ
→
seq
1
×
F
N
=
seq
1
×
F
N
−
1
F
N
29
1t1e1
⊢
1
⋅
1
=
1
30
29
a1i
⊢
A
∈
ℤ
∧
N
∈
ℙ
→
1
⋅
1
=
1
31
uz2m1nn
⊢
N
∈
ℤ
≥
2
→
N
−
1
∈
ℕ
32
23
31
syl
⊢
A
∈
ℤ
∧
N
∈
ℙ
→
N
−
1
∈
ℕ
33
nnuz
⊢
ℕ
=
ℤ
≥
1
34
32
33
eleqtrdi
⊢
A
∈
ℤ
∧
N
∈
ℙ
→
N
−
1
∈
ℤ
≥
1
35
elfznn
⊢
x
∈
1
…
N
−
1
→
x
∈
ℕ
36
35
adantl
⊢
A
∈
ℤ
∧
N
∈
ℙ
∧
x
∈
1
…
N
−
1
→
x
∈
ℕ
37
1
lgsfval
⊢
x
∈
ℕ
→
F
x
=
if
x
∈
ℙ
if
x
=
2
if
2
∥
A
0
if
A
mod
8
∈
1
7
1
−
1
A
x
−
1
2
+
1
mod
x
−
1
x
pCnt
N
1
38
36
37
syl
⊢
A
∈
ℤ
∧
N
∈
ℙ
∧
x
∈
1
…
N
−
1
→
F
x
=
if
x
∈
ℙ
if
x
=
2
if
2
∥
A
0
if
A
mod
8
∈
1
7
1
−
1
A
x
−
1
2
+
1
mod
x
−
1
x
pCnt
N
1
39
elfzelz
⊢
N
∈
1
…
N
−
1
→
N
∈
ℤ
40
39
zred
⊢
N
∈
1
…
N
−
1
→
N
∈
ℝ
41
40
ltm1d
⊢
N
∈
1
…
N
−
1
→
N
−
1
<
N
42
peano2rem
⊢
N
∈
ℝ
→
N
−
1
∈
ℝ
43
40
42
syl
⊢
N
∈
1
…
N
−
1
→
N
−
1
∈
ℝ
44
elfzle2
⊢
N
∈
1
…
N
−
1
→
N
≤
N
−
1
45
40
43
44
lensymd
⊢
N
∈
1
…
N
−
1
→
¬
N
−
1
<
N
46
41
45
pm2.65i
⊢
¬
N
∈
1
…
N
−
1
47
eleq1
⊢
x
=
N
→
x
∈
1
…
N
−
1
↔
N
∈
1
…
N
−
1
48
46
47
mtbiri
⊢
x
=
N
→
¬
x
∈
1
…
N
−
1
49
48
con2i
⊢
x
∈
1
…
N
−
1
→
¬
x
=
N
50
49
ad2antlr
⊢
A
∈
ℤ
∧
N
∈
ℙ
∧
x
∈
1
…
N
−
1
∧
x
∈
ℙ
→
¬
x
=
N
51
prmuz2
⊢
x
∈
ℙ
→
x
∈
ℤ
≥
2
52
simpllr
⊢
A
∈
ℤ
∧
N
∈
ℙ
∧
x
∈
1
…
N
−
1
∧
x
∈
ℙ
→
N
∈
ℙ
53
dvdsprm
⊢
x
∈
ℤ
≥
2
∧
N
∈
ℙ
→
x
∥
N
↔
x
=
N
54
51
52
53
syl2an2
⊢
A
∈
ℤ
∧
N
∈
ℙ
∧
x
∈
1
…
N
−
1
∧
x
∈
ℙ
→
x
∥
N
↔
x
=
N
55
50
54
mtbird
⊢
A
∈
ℤ
∧
N
∈
ℙ
∧
x
∈
1
…
N
−
1
∧
x
∈
ℙ
→
¬
x
∥
N
56
simpr
⊢
A
∈
ℤ
∧
N
∈
ℙ
∧
x
∈
1
…
N
−
1
∧
x
∈
ℙ
→
x
∈
ℙ
57
6
ad2antrr
⊢
A
∈
ℤ
∧
N
∈
ℙ
∧
x
∈
1
…
N
−
1
∧
x
∈
ℙ
→
N
∈
ℕ
58
pceq0
⊢
x
∈
ℙ
∧
N
∈
ℕ
→
x
pCnt
N
=
0
↔
¬
x
∥
N
59
56
57
58
syl2anc
⊢
A
∈
ℤ
∧
N
∈
ℙ
∧
x
∈
1
…
N
−
1
∧
x
∈
ℙ
→
x
pCnt
N
=
0
↔
¬
x
∥
N
60
55
59
mpbird
⊢
A
∈
ℤ
∧
N
∈
ℙ
∧
x
∈
1
…
N
−
1
∧
x
∈
ℙ
→
x
pCnt
N
=
0
61
60
oveq2d
⊢
A
∈
ℤ
∧
N
∈
ℙ
∧
x
∈
1
…
N
−
1
∧
x
∈
ℙ
→
if
x
=
2
if
2
∥
A
0
if
A
mod
8
∈
1
7
1
−
1
A
x
−
1
2
+
1
mod
x
−
1
x
pCnt
N
=
if
x
=
2
if
2
∥
A
0
if
A
mod
8
∈
1
7
1
−
1
A
x
−
1
2
+
1
mod
x
−
1
0
62
0z
⊢
0
∈
ℤ
63
neg1z
⊢
−
1
∈
ℤ
64
21
63
ifcli
⊢
if
A
mod
8
∈
1
7
1
−
1
∈
ℤ
65
62
64
ifcli
⊢
if
2
∥
A
0
if
A
mod
8
∈
1
7
1
−
1
∈
ℤ
66
65
a1i
⊢
A
∈
ℤ
∧
N
∈
ℙ
∧
x
∈
ℙ
∧
x
=
2
→
if
2
∥
A
0
if
A
mod
8
∈
1
7
1
−
1
∈
ℤ
67
simpl
⊢
A
∈
ℤ
∧
N
∈
ℙ
→
A
∈
ℤ
68
67
ad2antrr
⊢
A
∈
ℤ
∧
N
∈
ℙ
∧
x
∈
ℙ
∧
¬
x
=
2
→
A
∈
ℤ
69
simplr
⊢
A
∈
ℤ
∧
N
∈
ℙ
∧
x
∈
ℙ
∧
¬
x
=
2
→
x
∈
ℙ
70
simpr
⊢
A
∈
ℤ
∧
N
∈
ℙ
∧
x
∈
ℙ
∧
¬
x
=
2
→
¬
x
=
2
71
70
neqned
⊢
A
∈
ℤ
∧
N
∈
ℙ
∧
x
∈
ℙ
∧
¬
x
=
2
→
x
≠
2
72
eldifsn
⊢
x
∈
ℙ
∖
2
↔
x
∈
ℙ
∧
x
≠
2
73
69
71
72
sylanbrc
⊢
A
∈
ℤ
∧
N
∈
ℙ
∧
x
∈
ℙ
∧
¬
x
=
2
→
x
∈
ℙ
∖
2
74
oddprm
⊢
x
∈
ℙ
∖
2
→
x
−
1
2
∈
ℕ
75
73
74
syl
⊢
A
∈
ℤ
∧
N
∈
ℙ
∧
x
∈
ℙ
∧
¬
x
=
2
→
x
−
1
2
∈
ℕ
76
75
nnnn0d
⊢
A
∈
ℤ
∧
N
∈
ℙ
∧
x
∈
ℙ
∧
¬
x
=
2
→
x
−
1
2
∈
ℕ
0
77
zexpcl
⊢
A
∈
ℤ
∧
x
−
1
2
∈
ℕ
0
→
A
x
−
1
2
∈
ℤ
78
68
76
77
syl2anc
⊢
A
∈
ℤ
∧
N
∈
ℙ
∧
x
∈
ℙ
∧
¬
x
=
2
→
A
x
−
1
2
∈
ℤ
79
78
peano2zd
⊢
A
∈
ℤ
∧
N
∈
ℙ
∧
x
∈
ℙ
∧
¬
x
=
2
→
A
x
−
1
2
+
1
∈
ℤ
80
prmnn
⊢
x
∈
ℙ
→
x
∈
ℕ
81
80
ad2antlr
⊢
A
∈
ℤ
∧
N
∈
ℙ
∧
x
∈
ℙ
∧
¬
x
=
2
→
x
∈
ℕ
82
79
81
zmodcld
⊢
A
∈
ℤ
∧
N
∈
ℙ
∧
x
∈
ℙ
∧
¬
x
=
2
→
A
x
−
1
2
+
1
mod
x
∈
ℕ
0
83
82
nn0zd
⊢
A
∈
ℤ
∧
N
∈
ℙ
∧
x
∈
ℙ
∧
¬
x
=
2
→
A
x
−
1
2
+
1
mod
x
∈
ℤ
84
peano2zm
⊢
A
x
−
1
2
+
1
mod
x
∈
ℤ
→
A
x
−
1
2
+
1
mod
x
−
1
∈
ℤ
85
83
84
syl
⊢
A
∈
ℤ
∧
N
∈
ℙ
∧
x
∈
ℙ
∧
¬
x
=
2
→
A
x
−
1
2
+
1
mod
x
−
1
∈
ℤ
86
66
85
ifclda
⊢
A
∈
ℤ
∧
N
∈
ℙ
∧
x
∈
ℙ
→
if
x
=
2
if
2
∥
A
0
if
A
mod
8
∈
1
7
1
−
1
A
x
−
1
2
+
1
mod
x
−
1
∈
ℤ
87
86
zcnd
⊢
A
∈
ℤ
∧
N
∈
ℙ
∧
x
∈
ℙ
→
if
x
=
2
if
2
∥
A
0
if
A
mod
8
∈
1
7
1
−
1
A
x
−
1
2
+
1
mod
x
−
1
∈
ℂ
88
87
adantlr
⊢
A
∈
ℤ
∧
N
∈
ℙ
∧
x
∈
1
…
N
−
1
∧
x
∈
ℙ
→
if
x
=
2
if
2
∥
A
0
if
A
mod
8
∈
1
7
1
−
1
A
x
−
1
2
+
1
mod
x
−
1
∈
ℂ
89
88
exp0d
⊢
A
∈
ℤ
∧
N
∈
ℙ
∧
x
∈
1
…
N
−
1
∧
x
∈
ℙ
→
if
x
=
2
if
2
∥
A
0
if
A
mod
8
∈
1
7
1
−
1
A
x
−
1
2
+
1
mod
x
−
1
0
=
1
90
61
89
eqtrd
⊢
A
∈
ℤ
∧
N
∈
ℙ
∧
x
∈
1
…
N
−
1
∧
x
∈
ℙ
→
if
x
=
2
if
2
∥
A
0
if
A
mod
8
∈
1
7
1
−
1
A
x
−
1
2
+
1
mod
x
−
1
x
pCnt
N
=
1
91
90
ifeq1da
⊢
A
∈
ℤ
∧
N
∈
ℙ
∧
x
∈
1
…
N
−
1
→
if
x
∈
ℙ
if
x
=
2
if
2
∥
A
0
if
A
mod
8
∈
1
7
1
−
1
A
x
−
1
2
+
1
mod
x
−
1
x
pCnt
N
1
=
if
x
∈
ℙ
1
1
92
ifid
⊢
if
x
∈
ℙ
1
1
=
1
93
91
92
eqtrdi
⊢
A
∈
ℤ
∧
N
∈
ℙ
∧
x
∈
1
…
N
−
1
→
if
x
∈
ℙ
if
x
=
2
if
2
∥
A
0
if
A
mod
8
∈
1
7
1
−
1
A
x
−
1
2
+
1
mod
x
−
1
x
pCnt
N
1
=
1
94
38
93
eqtrd
⊢
A
∈
ℤ
∧
N
∈
ℙ
∧
x
∈
1
…
N
−
1
→
F
x
=
1
95
30
34
94
seqid3
⊢
A
∈
ℤ
∧
N
∈
ℙ
→
seq
1
×
F
N
−
1
=
1
96
95
oveq1d
⊢
A
∈
ℤ
∧
N
∈
ℙ
→
seq
1
×
F
N
−
1
F
N
=
1
F
N
97
2
adantl
⊢
A
∈
ℤ
∧
N
∈
ℙ
→
N
∈
ℤ
98
1
lgsfcl
⊢
A
∈
ℤ
∧
N
∈
ℤ
∧
N
≠
0
→
F
:
ℕ
⟶
ℤ
99
67
97
7
98
syl3anc
⊢
A
∈
ℤ
∧
N
∈
ℙ
→
F
:
ℕ
⟶
ℤ
100
99
6
ffvelcdmd
⊢
A
∈
ℤ
∧
N
∈
ℙ
→
F
N
∈
ℤ
101
100
zcnd
⊢
A
∈
ℤ
∧
N
∈
ℙ
→
F
N
∈
ℂ
102
101
mullidd
⊢
A
∈
ℤ
∧
N
∈
ℙ
→
1
F
N
=
F
N
103
28
96
102
3eqtrd
⊢
A
∈
ℤ
∧
N
∈
ℙ
→
seq
1
×
F
N
=
F
N
104
20
103
eqtrd
⊢
A
∈
ℤ
∧
N
∈
ℙ
→
seq
1
×
F
N
=
F
N
105
18
104
oveq12d
⊢
A
∈
ℤ
∧
N
∈
ℙ
→
if
N
<
0
∧
A
<
0
−
1
1
seq
1
×
F
N
=
1
F
N
106
1
lgsfval
⊢
N
∈
ℕ
→
F
N
=
if
N
∈
ℙ
if
N
=
2
if
2
∥
A
0
if
A
mod
8
∈
1
7
1
−
1
A
N
−
1
2
+
1
mod
N
−
1
N
pCnt
N
1
107
6
106
syl
⊢
A
∈
ℤ
∧
N
∈
ℙ
→
F
N
=
if
N
∈
ℙ
if
N
=
2
if
2
∥
A
0
if
A
mod
8
∈
1
7
1
−
1
A
N
−
1
2
+
1
mod
N
−
1
N
pCnt
N
1
108
iftrue
⊢
N
∈
ℙ
→
if
N
∈
ℙ
if
N
=
2
if
2
∥
A
0
if
A
mod
8
∈
1
7
1
−
1
A
N
−
1
2
+
1
mod
N
−
1
N
pCnt
N
1
=
if
N
=
2
if
2
∥
A
0
if
A
mod
8
∈
1
7
1
−
1
A
N
−
1
2
+
1
mod
N
−
1
N
pCnt
N
109
108
adantl
⊢
A
∈
ℤ
∧
N
∈
ℙ
→
if
N
∈
ℙ
if
N
=
2
if
2
∥
A
0
if
A
mod
8
∈
1
7
1
−
1
A
N
−
1
2
+
1
mod
N
−
1
N
pCnt
N
1
=
if
N
=
2
if
2
∥
A
0
if
A
mod
8
∈
1
7
1
−
1
A
N
−
1
2
+
1
mod
N
−
1
N
pCnt
N
110
6
nncnd
⊢
A
∈
ℤ
∧
N
∈
ℙ
→
N
∈
ℂ
111
110
exp1d
⊢
A
∈
ℤ
∧
N
∈
ℙ
→
N
1
=
N
112
111
oveq2d
⊢
A
∈
ℤ
∧
N
∈
ℙ
→
N
pCnt
N
1
=
N
pCnt
N
113
simpr
⊢
A
∈
ℤ
∧
N
∈
ℙ
→
N
∈
ℙ
114
pcid
⊢
N
∈
ℙ
∧
1
∈
ℤ
→
N
pCnt
N
1
=
1
115
113
21
114
sylancl
⊢
A
∈
ℤ
∧
N
∈
ℙ
→
N
pCnt
N
1
=
1
116
112
115
eqtr3d
⊢
A
∈
ℤ
∧
N
∈
ℙ
→
N
pCnt
N
=
1
117
116
oveq2d
⊢
A
∈
ℤ
∧
N
∈
ℙ
→
if
N
=
2
if
2
∥
A
0
if
A
mod
8
∈
1
7
1
−
1
A
N
−
1
2
+
1
mod
N
−
1
N
pCnt
N
=
if
N
=
2
if
2
∥
A
0
if
A
mod
8
∈
1
7
1
−
1
A
N
−
1
2
+
1
mod
N
−
1
1
118
eqeq1
⊢
x
=
N
→
x
=
2
↔
N
=
2
119
oveq1
⊢
x
=
N
→
x
−
1
=
N
−
1
120
119
oveq1d
⊢
x
=
N
→
x
−
1
2
=
N
−
1
2
121
120
oveq2d
⊢
x
=
N
→
A
x
−
1
2
=
A
N
−
1
2
122
121
oveq1d
⊢
x
=
N
→
A
x
−
1
2
+
1
=
A
N
−
1
2
+
1
123
id
⊢
x
=
N
→
x
=
N
124
122
123
oveq12d
⊢
x
=
N
→
A
x
−
1
2
+
1
mod
x
=
A
N
−
1
2
+
1
mod
N
125
124
oveq1d
⊢
x
=
N
→
A
x
−
1
2
+
1
mod
x
−
1
=
A
N
−
1
2
+
1
mod
N
−
1
126
118
125
ifbieq2d
⊢
x
=
N
→
if
x
=
2
if
2
∥
A
0
if
A
mod
8
∈
1
7
1
−
1
A
x
−
1
2
+
1
mod
x
−
1
=
if
N
=
2
if
2
∥
A
0
if
A
mod
8
∈
1
7
1
−
1
A
N
−
1
2
+
1
mod
N
−
1
127
126
eleq1d
⊢
x
=
N
→
if
x
=
2
if
2
∥
A
0
if
A
mod
8
∈
1
7
1
−
1
A
x
−
1
2
+
1
mod
x
−
1
∈
ℂ
↔
if
N
=
2
if
2
∥
A
0
if
A
mod
8
∈
1
7
1
−
1
A
N
−
1
2
+
1
mod
N
−
1
∈
ℂ
128
87
ralrimiva
⊢
A
∈
ℤ
∧
N
∈
ℙ
→
∀
x
∈
ℙ
if
x
=
2
if
2
∥
A
0
if
A
mod
8
∈
1
7
1
−
1
A
x
−
1
2
+
1
mod
x
−
1
∈
ℂ
129
127
128
113
rspcdva
⊢
A
∈
ℤ
∧
N
∈
ℙ
→
if
N
=
2
if
2
∥
A
0
if
A
mod
8
∈
1
7
1
−
1
A
N
−
1
2
+
1
mod
N
−
1
∈
ℂ
130
129
exp1d
⊢
A
∈
ℤ
∧
N
∈
ℙ
→
if
N
=
2
if
2
∥
A
0
if
A
mod
8
∈
1
7
1
−
1
A
N
−
1
2
+
1
mod
N
−
1
1
=
if
N
=
2
if
2
∥
A
0
if
A
mod
8
∈
1
7
1
−
1
A
N
−
1
2
+
1
mod
N
−
1
131
117
130
eqtrd
⊢
A
∈
ℤ
∧
N
∈
ℙ
→
if
N
=
2
if
2
∥
A
0
if
A
mod
8
∈
1
7
1
−
1
A
N
−
1
2
+
1
mod
N
−
1
N
pCnt
N
=
if
N
=
2
if
2
∥
A
0
if
A
mod
8
∈
1
7
1
−
1
A
N
−
1
2
+
1
mod
N
−
1
132
107
109
131
3eqtrd
⊢
A
∈
ℤ
∧
N
∈
ℙ
→
F
N
=
if
N
=
2
if
2
∥
A
0
if
A
mod
8
∈
1
7
1
−
1
A
N
−
1
2
+
1
mod
N
−
1
133
105
102
132
3eqtrd
⊢
A
∈
ℤ
∧
N
∈
ℙ
→
if
N
<
0
∧
A
<
0
−
1
1
seq
1
×
F
N
=
if
N
=
2
if
2
∥
A
0
if
A
mod
8
∈
1
7
1
−
1
A
N
−
1
2
+
1
mod
N
−
1
134
4
9
133
3eqtrd
⊢
A
∈
ℤ
∧
N
∈
ℙ
→
A
/
L
N
=
if
N
=
2
if
2
∥
A
0
if
A
mod
8
∈
1
7
1
−
1
A
N
−
1
2
+
1
mod
N
−
1