Theorem fntpb 7235

Description: A function whose domain has at most three elements can be represented as a set of at most three ordered pairs. (Contributed by AV, 26-Jan-2021.)

Hypotheses

Ref	Expression
fnprb.a	⊢ 𝐴 ∈ V
fnprb.b	⊢ 𝐵 ∈ V
fntpb.c	⊢ 𝐶 ∈ V

Assertion

Ref	Expression
fntpb	⊢ (𝐹 Fn {𝐴, 𝐵, 𝐶} ↔ 𝐹 = {⟨𝐴, (𝐹‘𝐴)⟩, ⟨𝐵, (𝐹‘𝐵)⟩, ⟨𝐶, (𝐹‘𝐶)⟩})

Proof of Theorem fntpb

Dummy variable 𝑥 is distinct from all other variables.

Step	Hyp	Ref	Expression
1		fnprb.a	. . . . . . . 8 ⊢ 𝐴 ∈ V
2		fnprb.b	. . . . . . . 8 ⊢ 𝐵 ∈ V
3	1, 2	fnprb 7234	. . . . . . 7 ⊢ (𝐹 Fn {𝐴, 𝐵} ↔ 𝐹 = {⟨𝐴, (𝐹‘𝐴)⟩, ⟨𝐵, (𝐹‘𝐵)⟩})
4		tpidm23 4718	. . . . . . . . 9 ⊢ {𝐴, 𝐵, 𝐵} = {𝐴, 𝐵}
5	4	eqcomi 2772	. . . . . . . 8 ⊢ {𝐴, 𝐵} = {𝐴, 𝐵, 𝐵}
6	5	fneq2i 6656	. . . . . . 7 ⊢ (𝐹 Fn {𝐴, 𝐵} ↔ 𝐹 Fn {𝐴, 𝐵, 𝐵})
7		tpidm23 4718	. . . . . . . . 9 ⊢ {⟨𝐴, (𝐹‘𝐴)⟩, ⟨𝐵, (𝐹‘𝐵)⟩, ⟨𝐵, (𝐹‘𝐵)⟩} = {⟨𝐴, (𝐹‘𝐴)⟩, ⟨𝐵, (𝐹‘𝐵)⟩}
8	7	eqcomi 2772	. . . . . . . 8 ⊢ {⟨𝐴, (𝐹‘𝐴)⟩, ⟨𝐵, (𝐹‘𝐵)⟩} = {⟨𝐴, (𝐹‘𝐴)⟩, ⟨𝐵, (𝐹‘𝐵)⟩, ⟨𝐵, (𝐹‘𝐵)⟩}
9	8	eqeq2i 2776	. . . . . . 7 ⊢ (𝐹 = {⟨𝐴, (𝐹‘𝐴)⟩, ⟨𝐵, (𝐹‘𝐵)⟩} ↔ 𝐹 = {⟨𝐴, (𝐹‘𝐴)⟩, ⟨𝐵, (𝐹‘𝐵)⟩, ⟨𝐵, (𝐹‘𝐵)⟩})
10	3, 6, 9	3bitr3i 304	. . . . . 6 ⊢ (𝐹 Fn {𝐴, 𝐵, 𝐵} ↔ 𝐹 = {⟨𝐴, (𝐹‘𝐴)⟩, ⟨𝐵, (𝐹‘𝐵)⟩, ⟨𝐵, (𝐹‘𝐵)⟩})
11	10	a1i 11	. . . . 5 ⊢ (𝐵 = 𝐶 → (𝐹 Fn {𝐴, 𝐵, 𝐵} ↔ 𝐹 = {⟨𝐴, (𝐹‘𝐴)⟩, ⟨𝐵, (𝐹‘𝐵)⟩, ⟨𝐵, (𝐹‘𝐵)⟩}))
12		tpeq3 4705	. . . . . 6 ⊢ (𝐵 = 𝐶 → {𝐴, 𝐵, 𝐵} = {𝐴, 𝐵, 𝐶})
13	12	fneq2d 6652	. . . . 5 ⊢ (𝐵 = 𝐶 → (𝐹 Fn {𝐴, 𝐵, 𝐵} ↔ 𝐹 Fn {𝐴, 𝐵, 𝐶}))
14		id 23	. . . . . . . 8 ⊢ (𝐵 = 𝐶 → 𝐵 = 𝐶)
15		fveq2 6905	. . . . . . . 8 ⊢ (𝐵 = 𝐶 → (𝐹‘𝐵) = (𝐹‘𝐶))
16	14, 15	opeq12d 4851	. . . . . . 7 ⊢ (𝐵 = 𝐶 → ⟨𝐵, (𝐹‘𝐵)⟩ = ⟨𝐶, (𝐹‘𝐶)⟩)
17	16	tpeq3d 4708	. . . . . 6 ⊢ (𝐵 = 𝐶 → {⟨𝐴, (𝐹‘𝐴)⟩, ⟨𝐵, (𝐹‘𝐵)⟩, ⟨𝐵, (𝐹‘𝐵)⟩} = {⟨𝐴, (𝐹‘𝐴)⟩, ⟨𝐵, (𝐹‘𝐵)⟩, ⟨𝐶, (𝐹‘𝐶)⟩})
18	17	eqeq2d 2774	. . . . 5 ⊢ (𝐵 = 𝐶 → (𝐹 = {⟨𝐴, (𝐹‘𝐴)⟩, ⟨𝐵, (𝐹‘𝐵)⟩, ⟨𝐵, (𝐹‘𝐵)⟩} ↔ 𝐹 = {⟨𝐴, (𝐹‘𝐴)⟩, ⟨𝐵, (𝐹‘𝐵)⟩, ⟨𝐶, (𝐹‘𝐶)⟩}))
19	11, 13, 18	3bitr3d 312	. . . 4 ⊢ (𝐵 = 𝐶 → (𝐹 Fn {𝐴, 𝐵, 𝐶} ↔ 𝐹 = {⟨𝐴, (𝐹‘𝐴)⟩, ⟨𝐵, (𝐹‘𝐵)⟩, ⟨𝐶, (𝐹‘𝐶)⟩}))
20	19	a1d 26	. . 3 ⊢ (𝐵 = 𝐶 → ((𝐴 ≠ 𝐵 ∧ 𝐴 ≠ 𝐶) → (𝐹 Fn {𝐴, 𝐵, 𝐶} ↔ 𝐹 = {⟨𝐴, (𝐹‘𝐴)⟩, ⟨𝐵, (𝐹‘𝐵)⟩, ⟨𝐶, (𝐹‘𝐶)⟩})))
21		fndm 6661	. . . . . . . 8 ⊢ (𝐹 Fn {𝐴, 𝐵, 𝐶} → dom 𝐹 = {𝐴, 𝐵, 𝐶})
22		fvex 6918	. . . . . . . . 9 ⊢ (𝐹‘𝐴) ∈ V
23		fvex 6918	. . . . . . . . 9 ⊢ (𝐹‘𝐵) ∈ V
24		fvex 6918	. . . . . . . . 9 ⊢ (𝐹‘𝐶) ∈ V
25	22, 23, 24	dmtpop 6231	. . . . . . . 8 ⊢ dom {⟨𝐴, (𝐹‘𝐴)⟩, ⟨𝐵, (𝐹‘𝐵)⟩, ⟨𝐶, (𝐹‘𝐶)⟩} = {𝐴, 𝐵, 𝐶}
26	21, 25	eqtr4di 2816	. . . . . . 7 ⊢ (𝐹 Fn {𝐴, 𝐵, 𝐶} → dom 𝐹 = dom {⟨𝐴, (𝐹‘𝐴)⟩, ⟨𝐵, (𝐹‘𝐵)⟩, ⟨𝐶, (𝐹‘𝐶)⟩})
27	26	adantl 487	. . . . . 6 ⊢ ((((𝐴 ≠ 𝐵 ∧ 𝐴 ≠ 𝐶) ∧ 𝐵 ≠ 𝐶) ∧ 𝐹 Fn {𝐴, 𝐵, 𝐶}) → dom 𝐹 = dom {⟨𝐴, (𝐹‘𝐴)⟩, ⟨𝐵, (𝐹‘𝐵)⟩, ⟨𝐶, (𝐹‘𝐶)⟩})
28	21	adantl 487	. . . . . . . . 9 ⊢ ((((𝐴 ≠ 𝐵 ∧ 𝐴 ≠ 𝐶) ∧ 𝐵 ≠ 𝐶) ∧ 𝐹 Fn {𝐴, 𝐵, 𝐶}) → dom 𝐹 = {𝐴, 𝐵, 𝐶})
29	28	eleq2d 2850	. . . . . . . 8 ⊢ ((((𝐴 ≠ 𝐵 ∧ 𝐴 ≠ 𝐶) ∧ 𝐵 ≠ 𝐶) ∧ 𝐹 Fn {𝐴, 𝐵, 𝐶}) → (𝑥 ∈ dom 𝐹 ↔ 𝑥 ∈ {𝐴, 𝐵, 𝐶}))
30		vex 3458	. . . . . . . . . 10 ⊢ 𝑥 ∈ V
31	30	eltp 4650	. . . . . . . . 9 ⊢ (𝑥 ∈ {𝐴, 𝐵, 𝐶} ↔ (𝑥 = 𝐴 ∨ 𝑥 = 𝐵 ∨ 𝑥 = 𝐶))
32	1, 22	fvtp1 7220	. . . . . . . . . . . . 13 ⊢ ((𝐴 ≠ 𝐵 ∧ 𝐴 ≠ 𝐶) → ({⟨𝐴, (𝐹‘𝐴)⟩, ⟨𝐵, (𝐹‘𝐵)⟩, ⟨𝐶, (𝐹‘𝐶)⟩}‘𝐴) = (𝐹‘𝐴))
33	32	ad2antrr 739	. . . . . . . . . . . 12 ⊢ ((((𝐴 ≠ 𝐵 ∧ 𝐴 ≠ 𝐶) ∧ 𝐵 ≠ 𝐶) ∧ 𝐹 Fn {𝐴, 𝐵, 𝐶}) → ({⟨𝐴, (𝐹‘𝐴)⟩, ⟨𝐵, (𝐹‘𝐵)⟩, ⟨𝐶, (𝐹‘𝐶)⟩}‘𝐴) = (𝐹‘𝐴))
34	33	eqcomd 2769	. . . . . . . . . . 11 ⊢ ((((𝐴 ≠ 𝐵 ∧ 𝐴 ≠ 𝐶) ∧ 𝐵 ≠ 𝐶) ∧ 𝐹 Fn {𝐴, 𝐵, 𝐶}) → (𝐹‘𝐴) = ({⟨𝐴, (𝐹‘𝐴)⟩, ⟨𝐵, (𝐹‘𝐵)⟩, ⟨𝐶, (𝐹‘𝐶)⟩}‘𝐴))
35		fveq2 6905	. . . . . . . . . . . 12 ⊢ (𝑥 = 𝐴 → (𝐹‘𝑥) = (𝐹‘𝐴))
36		fveq2 6905	. . . . . . . . . . . 12 ⊢ (𝑥 = 𝐴 → ({⟨𝐴, (𝐹‘𝐴)⟩, ⟨𝐵, (𝐹‘𝐵)⟩, ⟨𝐶, (𝐹‘𝐶)⟩}‘𝑥) = ({⟨𝐴, (𝐹‘𝐴)⟩, ⟨𝐵, (𝐹‘𝐵)⟩, ⟨𝐶, (𝐹‘𝐶)⟩}‘𝐴))
37	35, 36	eqeq12d 2779	. . . . . . . . . . 11 ⊢ (𝑥 = 𝐴 → ((𝐹‘𝑥) = ({⟨𝐴, (𝐹‘𝐴)⟩, ⟨𝐵, (𝐹‘𝐵)⟩, ⟨𝐶, (𝐹‘𝐶)⟩}‘𝑥) ↔ (𝐹‘𝐴) = ({⟨𝐴, (𝐹‘𝐴)⟩, ⟨𝐵, (𝐹‘𝐵)⟩, ⟨𝐶, (𝐹‘𝐶)⟩}‘𝐴)))
38	34, 37	syl5ibrcom 250	. . . . . . . . . 10 ⊢ ((((𝐴 ≠ 𝐵 ∧ 𝐴 ≠ 𝐶) ∧ 𝐵 ≠ 𝐶) ∧ 𝐹 Fn {𝐴, 𝐵, 𝐶}) → (𝑥 = 𝐴 → (𝐹‘𝑥) = ({⟨𝐴, (𝐹‘𝐴)⟩, ⟨𝐵, (𝐹‘𝐵)⟩, ⟨𝐶, (𝐹‘𝐶)⟩}‘𝑥)))
39	2, 23	fvtp2 7221	. . . . . . . . . . . . 13 ⊢ ((𝐴 ≠ 𝐵 ∧ 𝐵 ≠ 𝐶) → ({⟨𝐴, (𝐹‘𝐴)⟩, ⟨𝐵, (𝐹‘𝐵)⟩, ⟨𝐶, (𝐹‘𝐶)⟩}‘𝐵) = (𝐹‘𝐵))
40	39	ad4ant13 764	. . . . . . . . . . . 12 ⊢ ((((𝐴 ≠ 𝐵 ∧ 𝐴 ≠ 𝐶) ∧ 𝐵 ≠ 𝐶) ∧ 𝐹 Fn {𝐴, 𝐵, 𝐶}) → ({⟨𝐴, (𝐹‘𝐴)⟩, ⟨𝐵, (𝐹‘𝐵)⟩, ⟨𝐶, (𝐹‘𝐶)⟩}‘𝐵) = (𝐹‘𝐵))
41	40	eqcomd 2769	. . . . . . . . . . 11 ⊢ ((((𝐴 ≠ 𝐵 ∧ 𝐴 ≠ 𝐶) ∧ 𝐵 ≠ 𝐶) ∧ 𝐹 Fn {𝐴, 𝐵, 𝐶}) → (𝐹‘𝐵) = ({⟨𝐴, (𝐹‘𝐴)⟩, ⟨𝐵, (𝐹‘𝐵)⟩, ⟨𝐶, (𝐹‘𝐶)⟩}‘𝐵))
42		fveq2 6905	. . . . . . . . . . . 12 ⊢ (𝑥 = 𝐵 → (𝐹‘𝑥) = (𝐹‘𝐵))
43		fveq2 6905	. . . . . . . . . . . 12 ⊢ (𝑥 = 𝐵 → ({⟨𝐴, (𝐹‘𝐴)⟩, ⟨𝐵, (𝐹‘𝐵)⟩, ⟨𝐶, (𝐹‘𝐶)⟩}‘𝑥) = ({⟨𝐴, (𝐹‘𝐴)⟩, ⟨𝐵, (𝐹‘𝐵)⟩, ⟨𝐶, (𝐹‘𝐶)⟩}‘𝐵))
44	42, 43	eqeq12d 2779	. . . . . . . . . . 11 ⊢ (𝑥 = 𝐵 → ((𝐹‘𝑥) = ({⟨𝐴, (𝐹‘𝐴)⟩, ⟨𝐵, (𝐹‘𝐵)⟩, ⟨𝐶, (𝐹‘𝐶)⟩}‘𝑥) ↔ (𝐹‘𝐵) = ({⟨𝐴, (𝐹‘𝐴)⟩, ⟨𝐵, (𝐹‘𝐵)⟩, ⟨𝐶, (𝐹‘𝐶)⟩}‘𝐵)))
45	41, 44	syl5ibrcom 250	. . . . . . . . . 10 ⊢ ((((𝐴 ≠ 𝐵 ∧ 𝐴 ≠ 𝐶) ∧ 𝐵 ≠ 𝐶) ∧ 𝐹 Fn {𝐴, 𝐵, 𝐶}) → (𝑥 = 𝐵 → (𝐹‘𝑥) = ({⟨𝐴, (𝐹‘𝐴)⟩, ⟨𝐵, (𝐹‘𝐵)⟩, ⟨𝐶, (𝐹‘𝐶)⟩}‘𝑥)))
46		fntpb.c	. . . . . . . . . . . . . 14 ⊢ 𝐶 ∈ V
47	46, 24	fvtp3 7222	. . . . . . . . . . . . 13 ⊢ ((𝐴 ≠ 𝐶 ∧ 𝐵 ≠ 𝐶) → ({⟨𝐴, (𝐹‘𝐴)⟩, ⟨𝐵, (𝐹‘𝐵)⟩, ⟨𝐶, (𝐹‘𝐶)⟩}‘𝐶) = (𝐹‘𝐶))
48	47	ad4ant23 766	. . . . . . . . . . . 12 ⊢ ((((𝐴 ≠ 𝐵 ∧ 𝐴 ≠ 𝐶) ∧ 𝐵 ≠ 𝐶) ∧ 𝐹 Fn {𝐴, 𝐵, 𝐶}) → ({⟨𝐴, (𝐹‘𝐴)⟩, ⟨𝐵, (𝐹‘𝐵)⟩, ⟨𝐶, (𝐹‘𝐶)⟩}‘𝐶) = (𝐹‘𝐶))
49	48	eqcomd 2769	. . . . . . . . . . 11 ⊢ ((((𝐴 ≠ 𝐵 ∧ 𝐴 ≠ 𝐶) ∧ 𝐵 ≠ 𝐶) ∧ 𝐹 Fn {𝐴, 𝐵, 𝐶}) → (𝐹‘𝐶) = ({⟨𝐴, (𝐹‘𝐴)⟩, ⟨𝐵, (𝐹‘𝐵)⟩, ⟨𝐶, (𝐹‘𝐶)⟩}‘𝐶))
50		fveq2 6905	. . . . . . . . . . . 12 ⊢ (𝑥 = 𝐶 → (𝐹‘𝑥) = (𝐹‘𝐶))
51		fveq2 6905	. . . . . . . . . . . 12 ⊢ (𝑥 = 𝐶 → ({⟨𝐴, (𝐹‘𝐴)⟩, ⟨𝐵, (𝐹‘𝐵)⟩, ⟨𝐶, (𝐹‘𝐶)⟩}‘𝑥) = ({⟨𝐴, (𝐹‘𝐴)⟩, ⟨𝐵, (𝐹‘𝐵)⟩, ⟨𝐶, (𝐹‘𝐶)⟩}‘𝐶))
52	50, 51	eqeq12d 2779	. . . . . . . . . . 11 ⊢ (𝑥 = 𝐶 → ((𝐹‘𝑥) = ({⟨𝐴, (𝐹‘𝐴)⟩, ⟨𝐵, (𝐹‘𝐵)⟩, ⟨𝐶, (𝐹‘𝐶)⟩}‘𝑥) ↔ (𝐹‘𝐶) = ({⟨𝐴, (𝐹‘𝐴)⟩, ⟨𝐵, (𝐹‘𝐵)⟩, ⟨𝐶, (𝐹‘𝐶)⟩}‘𝐶)))
53	49, 52	syl5ibrcom 250	. . . . . . . . . 10 ⊢ ((((𝐴 ≠ 𝐵 ∧ 𝐴 ≠ 𝐶) ∧ 𝐵 ≠ 𝐶) ∧ 𝐹 Fn {𝐴, 𝐵, 𝐶}) → (𝑥 = 𝐶 → (𝐹‘𝑥) = ({⟨𝐴, (𝐹‘𝐴)⟩, ⟨𝐵, (𝐹‘𝐵)⟩, ⟨𝐶, (𝐹‘𝐶)⟩}‘𝑥)))
54	38, 45, 53	3jaod 1457	. . . . . . . . 9 ⊢ ((((𝐴 ≠ 𝐵 ∧ 𝐴 ≠ 𝐶) ∧ 𝐵 ≠ 𝐶) ∧ 𝐹 Fn {𝐴, 𝐵, 𝐶}) → ((𝑥 = 𝐴 ∨ 𝑥 = 𝐵 ∨ 𝑥 = 𝐶) → (𝐹‘𝑥) = ({⟨𝐴, (𝐹‘𝐴)⟩, ⟨𝐵, (𝐹‘𝐵)⟩, ⟨𝐶, (𝐹‘𝐶)⟩}‘𝑥)))
55	31, 54	biimtrid 245	. . . . . . . 8 ⊢ ((((𝐴 ≠ 𝐵 ∧ 𝐴 ≠ 𝐶) ∧ 𝐵 ≠ 𝐶) ∧ 𝐹 Fn {𝐴, 𝐵, 𝐶}) → (𝑥 ∈ {𝐴, 𝐵, 𝐶} → (𝐹‘𝑥) = ({⟨𝐴, (𝐹‘𝐴)⟩, ⟨𝐵, (𝐹‘𝐵)⟩, ⟨𝐶, (𝐹‘𝐶)⟩}‘𝑥)))
56	29, 55	sylbid 243	. . . . . . 7 ⊢ ((((𝐴 ≠ 𝐵 ∧ 𝐴 ≠ 𝐶) ∧ 𝐵 ≠ 𝐶) ∧ 𝐹 Fn {𝐴, 𝐵, 𝐶}) → (𝑥 ∈ dom 𝐹 → (𝐹‘𝑥) = ({⟨𝐴, (𝐹‘𝐴)⟩, ⟨𝐵, (𝐹‘𝐵)⟩, ⟨𝐶, (𝐹‘𝐶)⟩}‘𝑥)))
57	56	ralrimiv 3157	. . . . . 6 ⊢ ((((𝐴 ≠ 𝐵 ∧ 𝐴 ≠ 𝐶) ∧ 𝐵 ≠ 𝐶) ∧ 𝐹 Fn {𝐴, 𝐵, 𝐶}) → ∀𝑥 ∈ dom 𝐹(𝐹‘𝑥) = ({⟨𝐴, (𝐹‘𝐴)⟩, ⟨𝐵, (𝐹‘𝐵)⟩, ⟨𝐶, (𝐹‘𝐶)⟩}‘𝑥))
58		fnfun 6658	. . . . . . 7 ⊢ (𝐹 Fn {𝐴, 𝐵, 𝐶} → Fun 𝐹)
59	1, 2, 46, 22, 23, 24	funtp 6616	. . . . . . . 8 ⊢ ((𝐴 ≠ 𝐵 ∧ 𝐴 ≠ 𝐶 ∧ 𝐵 ≠ 𝐶) → Fun {⟨𝐴, (𝐹‘𝐴)⟩, ⟨𝐵, (𝐹‘𝐵)⟩, ⟨𝐶, (𝐹‘𝐶)⟩})
60	59	3expa 1136	. . . . . . 7 ⊢ (((𝐴 ≠ 𝐵 ∧ 𝐴 ≠ 𝐶) ∧ 𝐵 ≠ 𝐶) → Fun {⟨𝐴, (𝐹‘𝐴)⟩, ⟨𝐵, (𝐹‘𝐵)⟩, ⟨𝐶, (𝐹‘𝐶)⟩})
61		eqfunfv 7055	. . . . . . 7 ⊢ ((Fun 𝐹 ∧ Fun {⟨𝐴, (𝐹‘𝐴)⟩, ⟨𝐵, (𝐹‘𝐵)⟩, ⟨𝐶, (𝐹‘𝐶)⟩}) → (𝐹 = {⟨𝐴, (𝐹‘𝐴)⟩, ⟨𝐵, (𝐹‘𝐵)⟩, ⟨𝐶, (𝐹‘𝐶)⟩} ↔ (dom 𝐹 = dom {⟨𝐴, (𝐹‘𝐴)⟩, ⟨𝐵, (𝐹‘𝐵)⟩, ⟨𝐶, (𝐹‘𝐶)⟩} ∧ ∀𝑥 ∈ dom 𝐹(𝐹‘𝑥) = ({⟨𝐴, (𝐹‘𝐴)⟩, ⟨𝐵, (𝐹‘𝐵)⟩, ⟨𝐶, (𝐹‘𝐶)⟩}‘𝑥))))
62	58, 60, 61	syl2anr 609	. . . . . 6 ⊢ ((((𝐴 ≠ 𝐵 ∧ 𝐴 ≠ 𝐶) ∧ 𝐵 ≠ 𝐶) ∧ 𝐹 Fn {𝐴, 𝐵, 𝐶}) → (𝐹 = {⟨𝐴, (𝐹‘𝐴)⟩, ⟨𝐵, (𝐹‘𝐵)⟩, ⟨𝐶, (𝐹‘𝐶)⟩} ↔ (dom 𝐹 = dom {⟨𝐴, (𝐹‘𝐴)⟩, ⟨𝐵, (𝐹‘𝐵)⟩, ⟨𝐶, (𝐹‘𝐶)⟩} ∧ ∀𝑥 ∈ dom 𝐹(𝐹‘𝑥) = ({⟨𝐴, (𝐹‘𝐴)⟩, ⟨𝐵, (𝐹‘𝐵)⟩, ⟨𝐶, (𝐹‘𝐶)⟩}‘𝑥))))
63	27, 57, 62	mpbir2and 726	. . . . 5 ⊢ ((((𝐴 ≠ 𝐵 ∧ 𝐴 ≠ 𝐶) ∧ 𝐵 ≠ 𝐶) ∧ 𝐹 Fn {𝐴, 𝐵, 𝐶}) → 𝐹 = {⟨𝐴, (𝐹‘𝐴)⟩, ⟨𝐵, (𝐹‘𝐵)⟩, ⟨𝐶, (𝐹‘𝐶)⟩})
64	1, 2, 46, 22, 23, 24	fntp 6620	. . . . . . 7 ⊢ ((𝐴 ≠ 𝐵 ∧ 𝐴 ≠ 𝐶 ∧ 𝐵 ≠ 𝐶) → {⟨𝐴, (𝐹‘𝐴)⟩, ⟨𝐵, (𝐹‘𝐵)⟩, ⟨𝐶, (𝐹‘𝐶)⟩} Fn {𝐴, 𝐵, 𝐶})
65	64	3expa 1136	. . . . . 6 ⊢ (((𝐴 ≠ 𝐵 ∧ 𝐴 ≠ 𝐶) ∧ 𝐵 ≠ 𝐶) → {⟨𝐴, (𝐹‘𝐴)⟩, ⟨𝐵, (𝐹‘𝐵)⟩, ⟨𝐶, (𝐹‘𝐶)⟩} Fn {𝐴, 𝐵, 𝐶})
66		fneq1 6649	. . . . . . 7 ⊢ (𝐹 = {⟨𝐴, (𝐹‘𝐴)⟩, ⟨𝐵, (𝐹‘𝐵)⟩, ⟨𝐶, (𝐹‘𝐶)⟩} → (𝐹 Fn {𝐴, 𝐵, 𝐶} ↔ {⟨𝐴, (𝐹‘𝐴)⟩, ⟨𝐵, (𝐹‘𝐵)⟩, ⟨𝐶, (𝐹‘𝐶)⟩} Fn {𝐴, 𝐵, 𝐶}))
67	66	biimprd 251	. . . . . 6 ⊢ (𝐹 = {⟨𝐴, (𝐹‘𝐴)⟩, ⟨𝐵, (𝐹‘𝐵)⟩, ⟨𝐶, (𝐹‘𝐶)⟩} → ({⟨𝐴, (𝐹‘𝐴)⟩, ⟨𝐵, (𝐹‘𝐵)⟩, ⟨𝐶, (𝐹‘𝐶)⟩} Fn {𝐴, 𝐵, 𝐶} → 𝐹 Fn {𝐴, 𝐵, 𝐶}))
68	65, 67	mpan9 516	. . . . 5 ⊢ ((((𝐴 ≠ 𝐵 ∧ 𝐴 ≠ 𝐶) ∧ 𝐵 ≠ 𝐶) ∧ 𝐹 = {⟨𝐴, (𝐹‘𝐴)⟩, ⟨𝐵, (𝐹‘𝐵)⟩, ⟨𝐶, (𝐹‘𝐶)⟩}) → 𝐹 Fn {𝐴, 𝐵, 𝐶})
69	63, 68	impbida 813	. . . 4 ⊢ (((𝐴 ≠ 𝐵 ∧ 𝐴 ≠ 𝐶) ∧ 𝐵 ≠ 𝐶) → (𝐹 Fn {𝐴, 𝐵, 𝐶} ↔ 𝐹 = {⟨𝐴, (𝐹‘𝐴)⟩, ⟨𝐵, (𝐹‘𝐵)⟩, ⟨𝐶, (𝐹‘𝐶)⟩}))
70	69	expcom 419	. . 3 ⊢ (𝐵 ≠ 𝐶 → ((𝐴 ≠ 𝐵 ∧ 𝐴 ≠ 𝐶) → (𝐹 Fn {𝐴, 𝐵, 𝐶} ↔ 𝐹 = {⟨𝐴, (𝐹‘𝐴)⟩, ⟨𝐵, (𝐹‘𝐵)⟩, ⟨𝐶, (𝐹‘𝐶)⟩})))
71	20, 70	pm2.61ine 3042	. 2 ⊢ ((𝐴 ≠ 𝐵 ∧ 𝐴 ≠ 𝐶) → (𝐹 Fn {𝐴, 𝐵, 𝐶} ↔ 𝐹 = {⟨𝐴, (𝐹‘𝐴)⟩, ⟨𝐵, (𝐹‘𝐵)⟩, ⟨𝐶, (𝐹‘𝐶)⟩}))
72	1, 46	fnprb 7234	. . . . 5 ⊢ (𝐹 Fn {𝐴, 𝐶} ↔ 𝐹 = {⟨𝐴, (𝐹‘𝐴)⟩, ⟨𝐶, (𝐹‘𝐶)⟩})
73		tpidm12 4716	. . . . . . 7 ⊢ {𝐴, 𝐴, 𝐶} = {𝐴, 𝐶}
74	73	eqcomi 2772	. . . . . 6 ⊢ {𝐴, 𝐶} = {𝐴, 𝐴, 𝐶}
75	74	fneq2i 6656	. . . . 5 ⊢ (𝐹 Fn {𝐴, 𝐶} ↔ 𝐹 Fn {𝐴, 𝐴, 𝐶})
76		tpidm12 4716	. . . . . . 7 ⊢ {⟨𝐴, (𝐹‘𝐴)⟩, ⟨𝐴, (𝐹‘𝐴)⟩, ⟨𝐶, (𝐹‘𝐶)⟩} = {⟨𝐴, (𝐹‘𝐴)⟩, ⟨𝐶, (𝐹‘𝐶)⟩}
77	76	eqcomi 2772	. . . . . 6 ⊢ {⟨𝐴, (𝐹‘𝐴)⟩, ⟨𝐶, (𝐹‘𝐶)⟩} = {⟨𝐴, (𝐹‘𝐴)⟩, ⟨𝐴, (𝐹‘𝐴)⟩, ⟨𝐶, (𝐹‘𝐶)⟩}
78	77	eqeq2i 2776	. . . . 5 ⊢ (𝐹 = {⟨𝐴, (𝐹‘𝐴)⟩, ⟨𝐶, (𝐹‘𝐶)⟩} ↔ 𝐹 = {⟨𝐴, (𝐹‘𝐴)⟩, ⟨𝐴, (𝐹‘𝐴)⟩, ⟨𝐶, (𝐹‘𝐶)⟩})
79	72, 75, 78	3bitr3i 304	. . . 4 ⊢ (𝐹 Fn {𝐴, 𝐴, 𝐶} ↔ 𝐹 = {⟨𝐴, (𝐹‘𝐴)⟩, ⟨𝐴, (𝐹‘𝐴)⟩, ⟨𝐶, (𝐹‘𝐶)⟩})
80	79	a1i 11	. . 3 ⊢ (𝐴 = 𝐵 → (𝐹 Fn {𝐴, 𝐴, 𝐶} ↔ 𝐹 = {⟨𝐴, (𝐹‘𝐴)⟩, ⟨𝐴, (𝐹‘𝐴)⟩, ⟨𝐶, (𝐹‘𝐶)⟩}))
81		tpeq2 4704	. . . 4 ⊢ (𝐴 = 𝐵 → {𝐴, 𝐴, 𝐶} = {𝐴, 𝐵, 𝐶})
82	81	fneq2d 6652	. . 3 ⊢ (𝐴 = 𝐵 → (𝐹 Fn {𝐴, 𝐴, 𝐶} ↔ 𝐹 Fn {𝐴, 𝐵, 𝐶}))
83		id 23	. . . . . 6 ⊢ (𝐴 = 𝐵 → 𝐴 = 𝐵)
84		fveq2 6905	. . . . . 6 ⊢ (𝐴 = 𝐵 → (𝐹‘𝐴) = (𝐹‘𝐵))
85	83, 84	opeq12d 4851	. . . . 5 ⊢ (𝐴 = 𝐵 → ⟨𝐴, (𝐹‘𝐴)⟩ = ⟨𝐵, (𝐹‘𝐵)⟩)
86	85	tpeq2d 4707	. . . 4 ⊢ (𝐴 = 𝐵 → {⟨𝐴, (𝐹‘𝐴)⟩, ⟨𝐴, (𝐹‘𝐴)⟩, ⟨𝐶, (𝐹‘𝐶)⟩} = {⟨𝐴, (𝐹‘𝐴)⟩, ⟨𝐵, (𝐹‘𝐵)⟩, ⟨𝐶, (𝐹‘𝐶)⟩})
87	86	eqeq2d 2774	. . 3 ⊢ (𝐴 = 𝐵 → (𝐹 = {⟨𝐴, (𝐹‘𝐴)⟩, ⟨𝐴, (𝐹‘𝐴)⟩, ⟨𝐶, (𝐹‘𝐶)⟩} ↔ 𝐹 = {⟨𝐴, (𝐹‘𝐴)⟩, ⟨𝐵, (𝐹‘𝐵)⟩, ⟨𝐶, (𝐹‘𝐶)⟩}))
88	80, 82, 87	3bitr3d 312	. 2 ⊢ (𝐴 = 𝐵 → (𝐹 Fn {𝐴, 𝐵, 𝐶} ↔ 𝐹 = {⟨𝐴, (𝐹‘𝐴)⟩, ⟨𝐵, (𝐹‘𝐵)⟩, ⟨𝐶, (𝐹‘𝐶)⟩}))
89		tpidm13 4717	. . . . . . 7 ⊢ {𝐴, 𝐵, 𝐴} = {𝐴, 𝐵}
90	89	eqcomi 2772	. . . . . 6 ⊢ {𝐴, 𝐵} = {𝐴, 𝐵, 𝐴}
91	90	fneq2i 6656	. . . . 5 ⊢ (𝐹 Fn {𝐴, 𝐵} ↔ 𝐹 Fn {𝐴, 𝐵, 𝐴})
92		tpidm13 4717	. . . . . . 7 ⊢ {⟨𝐴, (𝐹‘𝐴)⟩, ⟨𝐵, (𝐹‘𝐵)⟩, ⟨𝐴, (𝐹‘𝐴)⟩} = {⟨𝐴, (𝐹‘𝐴)⟩, ⟨𝐵, (𝐹‘𝐵)⟩}
93	92	eqcomi 2772	. . . . . 6 ⊢ {⟨𝐴, (𝐹‘𝐴)⟩, ⟨𝐵, (𝐹‘𝐵)⟩} = {⟨𝐴, (𝐹‘𝐴)⟩, ⟨𝐵, (𝐹‘𝐵)⟩, ⟨𝐴, (𝐹‘𝐴)⟩}
94	93	eqeq2i 2776	. . . . 5 ⊢ (𝐹 = {⟨𝐴, (𝐹‘𝐴)⟩, ⟨𝐵, (𝐹‘𝐵)⟩} ↔ 𝐹 = {⟨𝐴, (𝐹‘𝐴)⟩, ⟨𝐵, (𝐹‘𝐵)⟩, ⟨𝐴, (𝐹‘𝐴)⟩})
95	3, 91, 94	3bitr3i 304	. . . 4 ⊢ (𝐹 Fn {𝐴, 𝐵, 𝐴} ↔ 𝐹 = {⟨𝐴, (𝐹‘𝐴)⟩, ⟨𝐵, (𝐹‘𝐵)⟩, ⟨𝐴, (𝐹‘𝐴)⟩})
96	95	a1i 11	. . 3 ⊢ (𝐴 = 𝐶 → (𝐹 Fn {𝐴, 𝐵, 𝐴} ↔ 𝐹 = {⟨𝐴, (𝐹‘𝐴)⟩, ⟨𝐵, (𝐹‘𝐵)⟩, ⟨𝐴, (𝐹‘𝐴)⟩}))
97		tpeq3 4705	. . . 4 ⊢ (𝐴 = 𝐶 → {𝐴, 𝐵, 𝐴} = {𝐴, 𝐵, 𝐶})
98	97	fneq2d 6652	. . 3 ⊢ (𝐴 = 𝐶 → (𝐹 Fn {𝐴, 𝐵, 𝐴} ↔ 𝐹 Fn {𝐴, 𝐵, 𝐶}))
99		id 23	. . . . . 6 ⊢ (𝐴 = 𝐶 → 𝐴 = 𝐶)
100		fveq2 6905	. . . . . 6 ⊢ (𝐴 = 𝐶 → (𝐹‘𝐴) = (𝐹‘𝐶))
101	99, 100	opeq12d 4851	. . . . 5 ⊢ (𝐴 = 𝐶 → ⟨𝐴, (𝐹‘𝐴)⟩ = ⟨𝐶, (𝐹‘𝐶)⟩)
102	101	tpeq3d 4708	. . . 4 ⊢ (𝐴 = 𝐶 → {⟨𝐴, (𝐹‘𝐴)⟩, ⟨𝐵, (𝐹‘𝐵)⟩, ⟨𝐴, (𝐹‘𝐴)⟩} = {⟨𝐴, (𝐹‘𝐴)⟩, ⟨𝐵, (𝐹‘𝐵)⟩, ⟨𝐶, (𝐹‘𝐶)⟩})
103	102	eqeq2d 2774	. . 3 ⊢ (𝐴 = 𝐶 → (𝐹 = {⟨𝐴, (𝐹‘𝐴)⟩, ⟨𝐵, (𝐹‘𝐵)⟩, ⟨𝐴, (𝐹‘𝐴)⟩} ↔ 𝐹 = {⟨𝐴, (𝐹‘𝐴)⟩, ⟨𝐵, (𝐹‘𝐵)⟩, ⟨𝐶, (𝐹‘𝐶)⟩}))
104	96, 98, 103	3bitr3d 312	. 2 ⊢ (𝐴 = 𝐶 → (𝐹 Fn {𝐴, 𝐵, 𝐶} ↔ 𝐹 = {⟨𝐴, (𝐹‘𝐴)⟩, ⟨𝐵, (𝐹‘𝐵)⟩, ⟨𝐶, (𝐹‘𝐶)⟩}))
105	71, 88, 104	pm2.61iine 3049	1 ⊢ (𝐹 Fn {𝐴, 𝐵, 𝐶} ↔ 𝐹 = {⟨𝐴, (𝐹‘𝐴)⟩, ⟨𝐵, (𝐹‘𝐵)⟩, ⟨𝐶, (𝐹‘𝐶)⟩})

This proof depends on syntax axioms:   → wi 4   ↔ wb 209   ∧ wa 401   ∨ w3o 1102   = wceq 1570   ∈ wcel 2147   ≠ wne 2959  ∀wral 3080  Vcvv 3454  {cpr 4590  {ctp 4592  ⟨cop 4838  dom cdm 5655  Fun wfun 6549   Fn wfn 6550  ‘cfv 6555

This proof depends on axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1828  ax-4 1842  ax-5 1945  ax-6 2002  ax-7 2043  ax-8 2149  ax-9 2157  ax-10 2180  ax-11 2197  ax-12 2216  ax-ext 2735  ax-sep 5252  ax-nul 5263  ax-pr 5395

This proof depends on definitions:  df-bi 210  df-an 402  df-or 862  df-3or 1104  df-3an 1105  df-tru 1573  df-fal 1583  df-ex 1813  df-nf 1817  df-sb 2102  df-mo 2567  df-eu 2597  df-clab 2742  df-cleq 2755  df-clel 2839  df-nfc 2913  df-ne 2960  df-ral 3081  df-rex 3091  df-reu 3370  df-rab 3417  df-v 3456  df-sbc 3743  df-csb 3852  df-ss 3901  df-dif 4050  df-in 4094  df-un 4154  df-nul 4282  df-if 4486  df-sn 4589  df-pr 4591  df-tp 4593  df-op 4839  df-uni 4871  df-br 5107  df-opab 5171  df-mpt 5190  df-id 5550  df-xp 5661  df-rel 5662  df-cnv 5663  df-co 5664  df-dm 5665  df-rn 5666  df-res 5667  df-ima 5668  df-iota 6509  df-fun 6557  df-fn 6558  df-f 6559  df-f1 6560  df-fo 6561  df-f1o 6562  df-fv 6563

This theorem is used by:  wrd3tpop  15125