Theorem lgsval 27423

Description: Value of the Legendre symbol at an arbitrary integer. (Contributed by Mario Carneiro, 4-Feb-2015.)

Hypothesis

Ref	Expression
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

Ref	Expression
lgsval	⊢ ((𝐴 ∈ ℤ ∧ 𝑁 ∈ ℤ) → (𝐴 /L 𝑁) = if(𝑁 = 0, if((𝐴↑2) = 1, 1, 0), (if((𝑁 < 0 ∧ 𝐴 < 0), -1, 1) · (seq1( · , 𝐹)‘(abs‘𝑁)))))

Distinct variable groups:   𝐴,𝑛   𝑛,𝑁

Allowed substitution hint:   𝐹(𝑛)

Proof of Theorem lgsval

Dummy variables 𝑎 𝑚 are mutually distinct and distinct from all other variables.

Step	Hyp	Ref	Expression
1		simpr 489	. . . 4 ⊢ ((𝑎 = 𝐴 ∧ 𝑚 = 𝑁) → 𝑚 = 𝑁)
2	1	eqeq1d 2767	. . 3 ⊢ ((𝑎 = 𝐴 ∧ 𝑚 = 𝑁) → (𝑚 = 0 ↔ 𝑁 = 0))
3		simpl 487	. . . . . 6 ⊢ ((𝑎 = 𝐴 ∧ 𝑚 = 𝑁) → 𝑎 = 𝐴)
4	3	oveq1d 7415	. . . . 5 ⊢ ((𝑎 = 𝐴 ∧ 𝑚 = 𝑁) → (𝑎↑2) = (𝐴↑2))
5	4	eqeq1d 2767	. . . 4 ⊢ ((𝑎 = 𝐴 ∧ 𝑚 = 𝑁) → ((𝑎↑2) = 1 ↔ (𝐴↑2) = 1))
6	5	ifbid 4507	. . 3 ⊢ ((𝑎 = 𝐴 ∧ 𝑚 = 𝑁) → if((𝑎↑2) = 1, 1, 0) = if((𝐴↑2) = 1, 1, 0))
7	1	breq1d 5115	. . . . . 6 ⊢ ((𝑎 = 𝐴 ∧ 𝑚 = 𝑁) → (𝑚 < 0 ↔ 𝑁 < 0))
8	3	breq1d 5115	. . . . . 6 ⊢ ((𝑎 = 𝐴 ∧ 𝑚 = 𝑁) → (𝑎 < 0 ↔ 𝐴 < 0))
9	7, 8	anbi12d 643	. . . . 5 ⊢ ((𝑎 = 𝐴 ∧ 𝑚 = 𝑁) → ((𝑚 < 0 ∧ 𝑎 < 0) ↔ (𝑁 < 0 ∧ 𝐴 < 0)))
10	9	ifbid 4507	. . . 4 ⊢ ((𝑎 = 𝐴 ∧ 𝑚 = 𝑁) → if((𝑚 < 0 ∧ 𝑎 < 0), -1, 1) = if((𝑁 < 0 ∧ 𝐴 < 0), -1, 1))
11	3	breq2d 5117	. . . . . . . . . . . 12 ⊢ ((𝑎 = 𝐴 ∧ 𝑚 = 𝑁) → (2 ∥ 𝑎 ↔ 2 ∥ 𝐴))
12	3	oveq1d 7415	. . . . . . . . . . . . . 14 ⊢ ((𝑎 = 𝐴 ∧ 𝑚 = 𝑁) → (𝑎 mod 8) = (𝐴 mod 8))
13	12	eleq1d 2850	. . . . . . . . . . . . 13 ⊢ ((𝑎 = 𝐴 ∧ 𝑚 = 𝑁) → ((𝑎 mod 8) ∈ {1, 7} ↔ (𝐴 mod 8) ∈ {1, 7}))
14	13	ifbid 4507	. . . . . . . . . . . 12 ⊢ ((𝑎 = 𝐴 ∧ 𝑚 = 𝑁) → if((𝑎 mod 8) ∈ {1, 7}, 1, -1) = if((𝐴 mod 8) ∈ {1, 7}, 1, -1))
15	11, 14	ifbieq2d 4510	. . . . . . . . . . 11 ⊢ ((𝑎 = 𝐴 ∧ 𝑚 = 𝑁) → if(2 ∥ 𝑎, 0, if((𝑎 mod 8) ∈ {1, 7}, 1, -1)) = if(2 ∥ 𝐴, 0, if((𝐴 mod 8) ∈ {1, 7}, 1, -1)))
16	3	oveq1d 7415	. . . . . . . . . . . . . 14 ⊢ ((𝑎 = 𝐴 ∧ 𝑚 = 𝑁) → (𝑎↑((𝑛 − 1) / 2)) = (𝐴↑((𝑛 − 1) / 2)))
17	16	oveq1d 7415	. . . . . . . . . . . . 13 ⊢ ((𝑎 = 𝐴 ∧ 𝑚 = 𝑁) → ((𝑎↑((𝑛 − 1) / 2)) + 1) = ((𝐴↑((𝑛 − 1) / 2)) + 1))
18	17	oveq1d 7415	. . . . . . . . . . . 12 ⊢ ((𝑎 = 𝐴 ∧ 𝑚 = 𝑁) → (((𝑎↑((𝑛 − 1) / 2)) + 1) mod 𝑛) = (((𝐴↑((𝑛 − 1) / 2)) + 1) mod 𝑛))
19	18	oveq1d 7415	. . . . . . . . . . 11 ⊢ ((𝑎 = 𝐴 ∧ 𝑚 = 𝑁) → ((((𝑎↑((𝑛 − 1) / 2)) + 1) mod 𝑛) − 1) = ((((𝐴↑((𝑛 − 1) / 2)) + 1) mod 𝑛) − 1))
20	15, 19	ifeq12d 4505	. . . . . . . . . 10 ⊢ ((𝑎 = 𝐴 ∧ 𝑚 = 𝑁) → if(𝑛 = 2, if(2 ∥ 𝑎, 0, if((𝑎 mod 8) ∈ {1, 7}, 1, -1)), ((((𝑎↑((𝑛 − 1) / 2)) + 1) mod 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)))
21	1	oveq2d 7416	. . . . . . . . . 10 ⊢ ((𝑎 = 𝐴 ∧ 𝑚 = 𝑁) → (𝑛 pCnt 𝑚) = (𝑛 pCnt 𝑁))
22	20, 21	oveq12d 7418	. . . . . . . . 9 ⊢ ((𝑎 = 𝐴 ∧ 𝑚 = 𝑁) → (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 𝑚)) = (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)))
23	22	ifeq1d 4503	. . . . . . . 8 ⊢ ((𝑎 = 𝐴 ∧ 𝑚 = 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 𝑚)), 1) = 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))
24	23	mpteq2dv 5199	. . . . . . 7 ⊢ ((𝑎 = 𝐴 ∧ 𝑚 = 𝑁) → (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 𝑚)), 1)) = (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)))
25		lgsval.1	. . . . . . 7 ⊢ 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))
26	24, 25	eqtr4di 2818	. . . . . 6 ⊢ ((𝑎 = 𝐴 ∧ 𝑚 = 𝑁) → (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 𝑚)), 1)) = 𝐹)
27	26	seqeq3d 14036	. . . . 5 ⊢ ((𝑎 = 𝐴 ∧ 𝑚 = 𝑁) → seq1( · , (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 𝑚)), 1))) = seq1( · , 𝐹))
28	1	fveq2d 6875	. . . . 5 ⊢ ((𝑎 = 𝐴 ∧ 𝑚 = 𝑁) → (abs‘𝑚) = (abs‘𝑁))
29	27, 28	fveq12d 6878	. . . 4 ⊢ ((𝑎 = 𝐴 ∧ 𝑚 = 𝑁) → (seq1( · , (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 𝑚)), 1)))‘(abs‘𝑚)) = (seq1( · , 𝐹)‘(abs‘𝑁)))
30	10, 29	oveq12d 7418	. . 3 ⊢ ((𝑎 = 𝐴 ∧ 𝑚 = 𝑁) → (if((𝑚 < 0 ∧ 𝑎 < 0), -1, 1) · (seq1( · , (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 𝑚)), 1)))‘(abs‘𝑚))) = (if((𝑁 < 0 ∧ 𝐴 < 0), -1, 1) · (seq1( · , 𝐹)‘(abs‘𝑁))))
31	2, 6, 30	ifbieq12d 4512	. 2 ⊢ ((𝑎 = 𝐴 ∧ 𝑚 = 𝑁) → if(𝑚 = 0, if((𝑎↑2) = 1, 1, 0), (if((𝑚 < 0 ∧ 𝑎 < 0), -1, 1) · (seq1( · , (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 𝑚)), 1)))‘(abs‘𝑚)))) = if(𝑁 = 0, if((𝐴↑2) = 1, 1, 0), (if((𝑁 < 0 ∧ 𝐴 < 0), -1, 1) · (seq1( · , 𝐹)‘(abs‘𝑁)))))
32		df-lgs 27417	. 2 ⊢ /L = (𝑎 ∈ ℤ, 𝑚 ∈ ℤ ↦ if(𝑚 = 0, if((𝑎↑2) = 1, 1, 0), (if((𝑚 < 0 ∧ 𝑎 < 0), -1, 1) · (seq1( · , (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 𝑚)), 1)))‘(abs‘𝑚)))))
33		1nn0 12511	. . . . 5 ⊢ 1 ∈ ℕ0
34		0nn0 12510	. . . . 5 ⊢ 0 ∈ ℕ0
35	33, 34	ifcli 4531	. . . 4 ⊢ if((𝐴↑2) = 1, 1, 0) ∈ ℕ0
36	35	elexi 3479	. . 3 ⊢ if((𝐴↑2) = 1, 1, 0) ∈ V
37		ovex 7433	. . 3 ⊢ (if((𝑁 < 0 ∧ 𝐴 < 0), -1, 1) · (seq1( · , 𝐹)‘(abs‘𝑁))) ∈ V
38	36, 37	ifex 4534	. 2 ⊢ if(𝑁 = 0, if((𝐴↑2) = 1, 1, 0), (if((𝑁 < 0 ∧ 𝐴 < 0), -1, 1) · (seq1( · , 𝐹)‘(abs‘𝑁)))) ∈ V
39	31, 32, 38	ovmpoa 7555	1 ⊢ ((𝐴 ∈ ℤ ∧ 𝑁 ∈ ℤ) → (𝐴 /L 𝑁) = if(𝑁 = 0, if((𝐴↑2) = 1, 1, 0), (if((𝑁 < 0 ∧ 𝐴 < 0), -1, 1) · (seq1( · , 𝐹)‘(abs‘𝑁)))))

Syntax hints:   → wi 4   ∧ wa 400   = wceq 1563   ∈ wcel 2145  ifcif 4483  {cpr 4587   class class class wbr 5105   ↦ cmpt 5186  ‘cfv 6525  (class class class)co 7400  0cc0 11088  1c1 11089   + caddc 11091   · cmul 11093   < clt 11231   − cmin 11429  -cneg 11430   / cdiv 11859  ℕcn 12224  2c2 12286  7c7 12291  8c8 12292  ℕ₀cn0 12495  ℤcz 12582   mod cmo 13893  seqcseq 14028  ↑cexp 14088  abscabs 15275   ∥ cdvds 16300  ℙcprime 16719   pCnt cpc 16886   /_L clgs 27416

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1818  ax-4 1832  ax-5 1933  ax-6 1990  ax-7 2031  ax-8 2147  ax-9 2155  ax-10 2178  ax-11 2194  ax-12 2215  ax-ext 2737  ax-sep 5251  ax-nul 5261  ax-pr 5395  ax-un 7722  ax-1cn 11146  ax-icn 11147  ax-addcl 11148  ax-mulcl 11150  ax-i2m1 11156

This theorem depends on definitions:  df-bi 210  df-an 401  df-or 861  df-3or 1102  df-3an 1103  df-tru 1566  df-fal 1576  df-ex 1803  df-nf 1807  df-sb 2094  df-mo 2569  df-eu 2599  df-clab 2744  df-cleq 2757  df-clel 2840  df-nfc 2914  df-ne 2961  df-ral 3080  df-rex 3090  df-reu 3371  df-rab 3418  df-v 3459  df-sbc 3748  df-csb 3856  df-dif 3910  df-un 3912  df-in 3914  df-ss 3924  df-pss 3927  df-nul 4289  df-if 4484  df-pw 4560  df-sn 4586  df-pr 4588  df-op 4592  df-uni 4869  df-iun 4954  df-br 5106  df-opab 5168  df-mpt 5187  df-tr 5213  df-id 5547  df-eprel 5552  df-po 5560  df-so 5561  df-fr 5605  df-we 5607  df-xp 5658  df-rel 5659  df-cnv 5660  df-co 5661  df-dm 5662  df-rn 5663  df-res 5664  df-ima 5665  df-pred 6292  df-ord 6353  df-on 6354  df-lim 6355  df-suc 6356  df-iota 6481  df-fun 6527  df-fn 6528  df-f 6529  df-f1 6530  df-fo 6531  df-f1o 6532  df-fv 6533  df-ov 7403  df-oprab 7404  df-mpo 7405  df-om 7851  df-2nd 7975  df-frecs 8266  df-wrecs 8297  df-recs 8346  df-rdg 8385  df-nn 12225  df-n0 12496  df-seq 14029  df-lgs 27417

This theorem is referenced by:  lgscllem  27426  lgsval2lem  27429  lgs0  27432  lgsval4  27439