Theorem pfxeq 41404

Description: The prefixes of two words are equal iff they have the same length and the same symbols at each position. Could replace swrdeq 13444. (Contributed by AV, 4-May-2020.)

Assertion

Ref	Expression
pfxeq	⊢ (((𝑊 ∈ Word 𝑉 ∧ 𝑈 ∈ Word 𝑉) ∧ (𝑀 ∈ ℕ0 ∧ 𝑁 ∈ ℕ0) ∧ (𝑀 ≤ (#‘𝑊) ∧ 𝑁 ≤ (#‘𝑈))) → ((𝑊 prefix 𝑀) = (𝑈 prefix 𝑁) ↔ (𝑀 = 𝑁 ∧ ∀𝑖 ∈ (0..^𝑀)(𝑊‘𝑖) = (𝑈‘𝑖))))

Distinct variable groups:   𝑖,𝑀   𝑖,𝑁   𝑈,𝑖   𝑖,𝑉   𝑖,𝑊

Proof of Theorem pfxeq

Step	Hyp	Ref	Expression
1		pfxcl 41386	. . . . 5 ⊢ (𝑊 ∈ Word 𝑉 → (𝑊 prefix 𝑀) ∈ Word 𝑉)
2		pfxcl 41386	. . . . 5 ⊢ (𝑈 ∈ Word 𝑉 → (𝑈 prefix 𝑁) ∈ Word 𝑉)
3	1, 2	anim12i 590	. . . 4 ⊢ ((𝑊 ∈ Word 𝑉 ∧ 𝑈 ∈ Word 𝑉) → ((𝑊 prefix 𝑀) ∈ Word 𝑉 ∧ (𝑈 prefix 𝑁) ∈ Word 𝑉))
4	3	3ad2ant1 1082	. . 3 ⊢ (((𝑊 ∈ Word 𝑉 ∧ 𝑈 ∈ Word 𝑉) ∧ (𝑀 ∈ ℕ0 ∧ 𝑁 ∈ ℕ0) ∧ (𝑀 ≤ (#‘𝑊) ∧ 𝑁 ≤ (#‘𝑈))) → ((𝑊 prefix 𝑀) ∈ Word 𝑉 ∧ (𝑈 prefix 𝑁) ∈ Word 𝑉))
5		eqwrd 13346	. . 3 ⊢ (((𝑊 prefix 𝑀) ∈ Word 𝑉 ∧ (𝑈 prefix 𝑁) ∈ Word 𝑉) → ((𝑊 prefix 𝑀) = (𝑈 prefix 𝑁) ↔ ((#‘(𝑊 prefix 𝑀)) = (#‘(𝑈 prefix 𝑁)) ∧ ∀𝑖 ∈ (0..^(#‘(𝑊 prefix 𝑀)))((𝑊 prefix 𝑀)‘𝑖) = ((𝑈 prefix 𝑁)‘𝑖))))
6	4, 5	syl 17	. 2 ⊢ (((𝑊 ∈ Word 𝑉 ∧ 𝑈 ∈ Word 𝑉) ∧ (𝑀 ∈ ℕ0 ∧ 𝑁 ∈ ℕ0) ∧ (𝑀 ≤ (#‘𝑊) ∧ 𝑁 ≤ (#‘𝑈))) → ((𝑊 prefix 𝑀) = (𝑈 prefix 𝑁) ↔ ((#‘(𝑊 prefix 𝑀)) = (#‘(𝑈 prefix 𝑁)) ∧ ∀𝑖 ∈ (0..^(#‘(𝑊 prefix 𝑀)))((𝑊 prefix 𝑀)‘𝑖) = ((𝑈 prefix 𝑁)‘𝑖))))
7		simpl 473	. . . . . 6 ⊢ ((𝑊 ∈ Word 𝑉 ∧ 𝑈 ∈ Word 𝑉) → 𝑊 ∈ Word 𝑉)
8	7	3ad2ant1 1082	. . . . 5 ⊢ (((𝑊 ∈ Word 𝑉 ∧ 𝑈 ∈ Word 𝑉) ∧ (𝑀 ∈ ℕ0 ∧ 𝑁 ∈ ℕ0) ∧ (𝑀 ≤ (#‘𝑊) ∧ 𝑁 ≤ (#‘𝑈))) → 𝑊 ∈ Word 𝑉)
9		simpl 473	. . . . . . 7 ⊢ ((𝑀 ∈ ℕ0 ∧ 𝑁 ∈ ℕ0) → 𝑀 ∈ ℕ0)
10	9	3ad2ant2 1083	. . . . . 6 ⊢ (((𝑊 ∈ Word 𝑉 ∧ 𝑈 ∈ Word 𝑉) ∧ (𝑀 ∈ ℕ0 ∧ 𝑁 ∈ ℕ0) ∧ (𝑀 ≤ (#‘𝑊) ∧ 𝑁 ≤ (#‘𝑈))) → 𝑀 ∈ ℕ0)
11		lencl 13324	. . . . . . . 8 ⊢ (𝑊 ∈ Word 𝑉 → (#‘𝑊) ∈ ℕ0)
12	11	adantr 481	. . . . . . 7 ⊢ ((𝑊 ∈ Word 𝑉 ∧ 𝑈 ∈ Word 𝑉) → (#‘𝑊) ∈ ℕ0)
13	12	3ad2ant1 1082	. . . . . 6 ⊢ (((𝑊 ∈ Word 𝑉 ∧ 𝑈 ∈ Word 𝑉) ∧ (𝑀 ∈ ℕ0 ∧ 𝑁 ∈ ℕ0) ∧ (𝑀 ≤ (#‘𝑊) ∧ 𝑁 ≤ (#‘𝑈))) → (#‘𝑊) ∈ ℕ0)
14		simpl 473	. . . . . . 7 ⊢ ((𝑀 ≤ (#‘𝑊) ∧ 𝑁 ≤ (#‘𝑈)) → 𝑀 ≤ (#‘𝑊))
15	14	3ad2ant3 1084	. . . . . 6 ⊢ (((𝑊 ∈ Word 𝑉 ∧ 𝑈 ∈ Word 𝑉) ∧ (𝑀 ∈ ℕ0 ∧ 𝑁 ∈ ℕ0) ∧ (𝑀 ≤ (#‘𝑊) ∧ 𝑁 ≤ (#‘𝑈))) → 𝑀 ≤ (#‘𝑊))
16		elfz2nn0 12431	. . . . . 6 ⊢ (𝑀 ∈ (0...(#‘𝑊)) ↔ (𝑀 ∈ ℕ0 ∧ (#‘𝑊) ∈ ℕ0 ∧ 𝑀 ≤ (#‘𝑊)))
17	10, 13, 15, 16	syl3anbrc 1246	. . . . 5 ⊢ (((𝑊 ∈ Word 𝑉 ∧ 𝑈 ∈ Word 𝑉) ∧ (𝑀 ∈ ℕ0 ∧ 𝑁 ∈ ℕ0) ∧ (𝑀 ≤ (#‘𝑊) ∧ 𝑁 ≤ (#‘𝑈))) → 𝑀 ∈ (0...(#‘𝑊)))
18		pfxlen 41391	. . . . 5 ⊢ ((𝑊 ∈ Word 𝑉 ∧ 𝑀 ∈ (0...(#‘𝑊))) → (#‘(𝑊 prefix 𝑀)) = 𝑀)
19	8, 17, 18	syl2anc 693	. . . 4 ⊢ (((𝑊 ∈ Word 𝑉 ∧ 𝑈 ∈ Word 𝑉) ∧ (𝑀 ∈ ℕ0 ∧ 𝑁 ∈ ℕ0) ∧ (𝑀 ≤ (#‘𝑊) ∧ 𝑁 ≤ (#‘𝑈))) → (#‘(𝑊 prefix 𝑀)) = 𝑀)
20		simpr 477	. . . . . 6 ⊢ ((𝑊 ∈ Word 𝑉 ∧ 𝑈 ∈ Word 𝑉) → 𝑈 ∈ Word 𝑉)
21	20	3ad2ant1 1082	. . . . 5 ⊢ (((𝑊 ∈ Word 𝑉 ∧ 𝑈 ∈ Word 𝑉) ∧ (𝑀 ∈ ℕ0 ∧ 𝑁 ∈ ℕ0) ∧ (𝑀 ≤ (#‘𝑊) ∧ 𝑁 ≤ (#‘𝑈))) → 𝑈 ∈ Word 𝑉)
22		simpr 477	. . . . . . 7 ⊢ ((𝑀 ∈ ℕ0 ∧ 𝑁 ∈ ℕ0) → 𝑁 ∈ ℕ0)
23	22	3ad2ant2 1083	. . . . . 6 ⊢ (((𝑊 ∈ Word 𝑉 ∧ 𝑈 ∈ Word 𝑉) ∧ (𝑀 ∈ ℕ0 ∧ 𝑁 ∈ ℕ0) ∧ (𝑀 ≤ (#‘𝑊) ∧ 𝑁 ≤ (#‘𝑈))) → 𝑁 ∈ ℕ0)
24		lencl 13324	. . . . . . . 8 ⊢ (𝑈 ∈ Word 𝑉 → (#‘𝑈) ∈ ℕ0)
25	24	adantl 482	. . . . . . 7 ⊢ ((𝑊 ∈ Word 𝑉 ∧ 𝑈 ∈ Word 𝑉) → (#‘𝑈) ∈ ℕ0)
26	25	3ad2ant1 1082	. . . . . 6 ⊢ (((𝑊 ∈ Word 𝑉 ∧ 𝑈 ∈ Word 𝑉) ∧ (𝑀 ∈ ℕ0 ∧ 𝑁 ∈ ℕ0) ∧ (𝑀 ≤ (#‘𝑊) ∧ 𝑁 ≤ (#‘𝑈))) → (#‘𝑈) ∈ ℕ0)
27		simpr 477	. . . . . . 7 ⊢ ((𝑀 ≤ (#‘𝑊) ∧ 𝑁 ≤ (#‘𝑈)) → 𝑁 ≤ (#‘𝑈))
28	27	3ad2ant3 1084	. . . . . 6 ⊢ (((𝑊 ∈ Word 𝑉 ∧ 𝑈 ∈ Word 𝑉) ∧ (𝑀 ∈ ℕ0 ∧ 𝑁 ∈ ℕ0) ∧ (𝑀 ≤ (#‘𝑊) ∧ 𝑁 ≤ (#‘𝑈))) → 𝑁 ≤ (#‘𝑈))
29		elfz2nn0 12431	. . . . . 6 ⊢ (𝑁 ∈ (0...(#‘𝑈)) ↔ (𝑁 ∈ ℕ0 ∧ (#‘𝑈) ∈ ℕ0 ∧ 𝑁 ≤ (#‘𝑈)))
30	23, 26, 28, 29	syl3anbrc 1246	. . . . 5 ⊢ (((𝑊 ∈ Word 𝑉 ∧ 𝑈 ∈ Word 𝑉) ∧ (𝑀 ∈ ℕ0 ∧ 𝑁 ∈ ℕ0) ∧ (𝑀 ≤ (#‘𝑊) ∧ 𝑁 ≤ (#‘𝑈))) → 𝑁 ∈ (0...(#‘𝑈)))
31		pfxlen 41391	. . . . 5 ⊢ ((𝑈 ∈ Word 𝑉 ∧ 𝑁 ∈ (0...(#‘𝑈))) → (#‘(𝑈 prefix 𝑁)) = 𝑁)
32	21, 30, 31	syl2anc 693	. . . 4 ⊢ (((𝑊 ∈ Word 𝑉 ∧ 𝑈 ∈ Word 𝑉) ∧ (𝑀 ∈ ℕ0 ∧ 𝑁 ∈ ℕ0) ∧ (𝑀 ≤ (#‘𝑊) ∧ 𝑁 ≤ (#‘𝑈))) → (#‘(𝑈 prefix 𝑁)) = 𝑁)
33	19, 32	eqeq12d 2637	. . 3 ⊢ (((𝑊 ∈ Word 𝑉 ∧ 𝑈 ∈ Word 𝑉) ∧ (𝑀 ∈ ℕ0 ∧ 𝑁 ∈ ℕ0) ∧ (𝑀 ≤ (#‘𝑊) ∧ 𝑁 ≤ (#‘𝑈))) → ((#‘(𝑊 prefix 𝑀)) = (#‘(𝑈 prefix 𝑁)) ↔ 𝑀 = 𝑁))
34	33	anbi1d 741	. 2 ⊢ (((𝑊 ∈ Word 𝑉 ∧ 𝑈 ∈ Word 𝑉) ∧ (𝑀 ∈ ℕ0 ∧ 𝑁 ∈ ℕ0) ∧ (𝑀 ≤ (#‘𝑊) ∧ 𝑁 ≤ (#‘𝑈))) → (((#‘(𝑊 prefix 𝑀)) = (#‘(𝑈 prefix 𝑁)) ∧ ∀𝑖 ∈ (0..^(#‘(𝑊 prefix 𝑀)))((𝑊 prefix 𝑀)‘𝑖) = ((𝑈 prefix 𝑁)‘𝑖)) ↔ (𝑀 = 𝑁 ∧ ∀𝑖 ∈ (0..^(#‘(𝑊 prefix 𝑀)))((𝑊 prefix 𝑀)‘𝑖) = ((𝑈 prefix 𝑁)‘𝑖))))
35	8	adantr 481	. . . . . . 7 ⊢ ((((𝑊 ∈ Word 𝑉 ∧ 𝑈 ∈ Word 𝑉) ∧ (𝑀 ∈ ℕ0 ∧ 𝑁 ∈ ℕ0) ∧ (𝑀 ≤ (#‘𝑊) ∧ 𝑁 ≤ (#‘𝑈))) ∧ 𝑀 = 𝑁) → 𝑊 ∈ Word 𝑉)
36	17	adantr 481	. . . . . . 7 ⊢ ((((𝑊 ∈ Word 𝑉 ∧ 𝑈 ∈ Word 𝑉) ∧ (𝑀 ∈ ℕ0 ∧ 𝑁 ∈ ℕ0) ∧ (𝑀 ≤ (#‘𝑊) ∧ 𝑁 ≤ (#‘𝑈))) ∧ 𝑀 = 𝑁) → 𝑀 ∈ (0...(#‘𝑊)))
37	35, 36, 18	syl2anc 693	. . . . . 6 ⊢ ((((𝑊 ∈ Word 𝑉 ∧ 𝑈 ∈ Word 𝑉) ∧ (𝑀 ∈ ℕ0 ∧ 𝑁 ∈ ℕ0) ∧ (𝑀 ≤ (#‘𝑊) ∧ 𝑁 ≤ (#‘𝑈))) ∧ 𝑀 = 𝑁) → (#‘(𝑊 prefix 𝑀)) = 𝑀)
38	37	oveq2d 6666	. . . . 5 ⊢ ((((𝑊 ∈ Word 𝑉 ∧ 𝑈 ∈ Word 𝑉) ∧ (𝑀 ∈ ℕ0 ∧ 𝑁 ∈ ℕ0) ∧ (𝑀 ≤ (#‘𝑊) ∧ 𝑁 ≤ (#‘𝑈))) ∧ 𝑀 = 𝑁) → (0..^(#‘(𝑊 prefix 𝑀))) = (0..^𝑀))
39	38	raleqdv 3144	. . . 4 ⊢ ((((𝑊 ∈ Word 𝑉 ∧ 𝑈 ∈ Word 𝑉) ∧ (𝑀 ∈ ℕ0 ∧ 𝑁 ∈ ℕ0) ∧ (𝑀 ≤ (#‘𝑊) ∧ 𝑁 ≤ (#‘𝑈))) ∧ 𝑀 = 𝑁) → (∀𝑖 ∈ (0..^(#‘(𝑊 prefix 𝑀)))((𝑊 prefix 𝑀)‘𝑖) = ((𝑈 prefix 𝑁)‘𝑖) ↔ ∀𝑖 ∈ (0..^𝑀)((𝑊 prefix 𝑀)‘𝑖) = ((𝑈 prefix 𝑁)‘𝑖)))
40	35	adantr 481	. . . . . . 7 ⊢ (((((𝑊 ∈ Word 𝑉 ∧ 𝑈 ∈ Word 𝑉) ∧ (𝑀 ∈ ℕ0 ∧ 𝑁 ∈ ℕ0) ∧ (𝑀 ≤ (#‘𝑊) ∧ 𝑁 ≤ (#‘𝑈))) ∧ 𝑀 = 𝑁) ∧ 𝑖 ∈ (0..^𝑀)) → 𝑊 ∈ Word 𝑉)
41	36	adantr 481	. . . . . . 7 ⊢ (((((𝑊 ∈ Word 𝑉 ∧ 𝑈 ∈ Word 𝑉) ∧ (𝑀 ∈ ℕ0 ∧ 𝑁 ∈ ℕ0) ∧ (𝑀 ≤ (#‘𝑊) ∧ 𝑁 ≤ (#‘𝑈))) ∧ 𝑀 = 𝑁) ∧ 𝑖 ∈ (0..^𝑀)) → 𝑀 ∈ (0...(#‘𝑊)))
42		simpr 477	. . . . . . 7 ⊢ (((((𝑊 ∈ Word 𝑉 ∧ 𝑈 ∈ Word 𝑉) ∧ (𝑀 ∈ ℕ0 ∧ 𝑁 ∈ ℕ0) ∧ (𝑀 ≤ (#‘𝑊) ∧ 𝑁 ≤ (#‘𝑈))) ∧ 𝑀 = 𝑁) ∧ 𝑖 ∈ (0..^𝑀)) → 𝑖 ∈ (0..^𝑀))
43		pfxfv 41399	. . . . . . 7 ⊢ ((𝑊 ∈ Word 𝑉 ∧ 𝑀 ∈ (0...(#‘𝑊)) ∧ 𝑖 ∈ (0..^𝑀)) → ((𝑊 prefix 𝑀)‘𝑖) = (𝑊‘𝑖))
44	40, 41, 42, 43	syl3anc 1326	. . . . . 6 ⊢ (((((𝑊 ∈ Word 𝑉 ∧ 𝑈 ∈ Word 𝑉) ∧ (𝑀 ∈ ℕ0 ∧ 𝑁 ∈ ℕ0) ∧ (𝑀 ≤ (#‘𝑊) ∧ 𝑁 ≤ (#‘𝑈))) ∧ 𝑀 = 𝑁) ∧ 𝑖 ∈ (0..^𝑀)) → ((𝑊 prefix 𝑀)‘𝑖) = (𝑊‘𝑖))
45	21	ad2antrr 762	. . . . . . 7 ⊢ (((((𝑊 ∈ Word 𝑉 ∧ 𝑈 ∈ Word 𝑉) ∧ (𝑀 ∈ ℕ0 ∧ 𝑁 ∈ ℕ0) ∧ (𝑀 ≤ (#‘𝑊) ∧ 𝑁 ≤ (#‘𝑈))) ∧ 𝑀 = 𝑁) ∧ 𝑖 ∈ (0..^𝑀)) → 𝑈 ∈ Word 𝑉)
46	30	ad2antrr 762	. . . . . . 7 ⊢ (((((𝑊 ∈ Word 𝑉 ∧ 𝑈 ∈ Word 𝑉) ∧ (𝑀 ∈ ℕ0 ∧ 𝑁 ∈ ℕ0) ∧ (𝑀 ≤ (#‘𝑊) ∧ 𝑁 ≤ (#‘𝑈))) ∧ 𝑀 = 𝑁) ∧ 𝑖 ∈ (0..^𝑀)) → 𝑁 ∈ (0...(#‘𝑈)))
47		oveq2 6658	. . . . . . . . . 10 ⊢ (𝑀 = 𝑁 → (0..^𝑀) = (0..^𝑁))
48	47	eleq2d 2687	. . . . . . . . 9 ⊢ (𝑀 = 𝑁 → (𝑖 ∈ (0..^𝑀) ↔ 𝑖 ∈ (0..^𝑁)))
49	48	adantl 482	. . . . . . . 8 ⊢ ((((𝑊 ∈ Word 𝑉 ∧ 𝑈 ∈ Word 𝑉) ∧ (𝑀 ∈ ℕ0 ∧ 𝑁 ∈ ℕ0) ∧ (𝑀 ≤ (#‘𝑊) ∧ 𝑁 ≤ (#‘𝑈))) ∧ 𝑀 = 𝑁) → (𝑖 ∈ (0..^𝑀) ↔ 𝑖 ∈ (0..^𝑁)))
50	49	biimpa 501	. . . . . . 7 ⊢ (((((𝑊 ∈ Word 𝑉 ∧ 𝑈 ∈ Word 𝑉) ∧ (𝑀 ∈ ℕ0 ∧ 𝑁 ∈ ℕ0) ∧ (𝑀 ≤ (#‘𝑊) ∧ 𝑁 ≤ (#‘𝑈))) ∧ 𝑀 = 𝑁) ∧ 𝑖 ∈ (0..^𝑀)) → 𝑖 ∈ (0..^𝑁))
51		pfxfv 41399	. . . . . . 7 ⊢ ((𝑈 ∈ Word 𝑉 ∧ 𝑁 ∈ (0...(#‘𝑈)) ∧ 𝑖 ∈ (0..^𝑁)) → ((𝑈 prefix 𝑁)‘𝑖) = (𝑈‘𝑖))
52	45, 46, 50, 51	syl3anc 1326	. . . . . 6 ⊢ (((((𝑊 ∈ Word 𝑉 ∧ 𝑈 ∈ Word 𝑉) ∧ (𝑀 ∈ ℕ0 ∧ 𝑁 ∈ ℕ0) ∧ (𝑀 ≤ (#‘𝑊) ∧ 𝑁 ≤ (#‘𝑈))) ∧ 𝑀 = 𝑁) ∧ 𝑖 ∈ (0..^𝑀)) → ((𝑈 prefix 𝑁)‘𝑖) = (𝑈‘𝑖))
53	44, 52	eqeq12d 2637	. . . . 5 ⊢ (((((𝑊 ∈ Word 𝑉 ∧ 𝑈 ∈ Word 𝑉) ∧ (𝑀 ∈ ℕ0 ∧ 𝑁 ∈ ℕ0) ∧ (𝑀 ≤ (#‘𝑊) ∧ 𝑁 ≤ (#‘𝑈))) ∧ 𝑀 = 𝑁) ∧ 𝑖 ∈ (0..^𝑀)) → (((𝑊 prefix 𝑀)‘𝑖) = ((𝑈 prefix 𝑁)‘𝑖) ↔ (𝑊‘𝑖) = (𝑈‘𝑖)))
54	53	ralbidva 2985	. . . 4 ⊢ ((((𝑊 ∈ Word 𝑉 ∧ 𝑈 ∈ Word 𝑉) ∧ (𝑀 ∈ ℕ0 ∧ 𝑁 ∈ ℕ0) ∧ (𝑀 ≤ (#‘𝑊) ∧ 𝑁 ≤ (#‘𝑈))) ∧ 𝑀 = 𝑁) → (∀𝑖 ∈ (0..^𝑀)((𝑊 prefix 𝑀)‘𝑖) = ((𝑈 prefix 𝑁)‘𝑖) ↔ ∀𝑖 ∈ (0..^𝑀)(𝑊‘𝑖) = (𝑈‘𝑖)))
55	39, 54	bitrd 268	. . 3 ⊢ ((((𝑊 ∈ Word 𝑉 ∧ 𝑈 ∈ Word 𝑉) ∧ (𝑀 ∈ ℕ0 ∧ 𝑁 ∈ ℕ0) ∧ (𝑀 ≤ (#‘𝑊) ∧ 𝑁 ≤ (#‘𝑈))) ∧ 𝑀 = 𝑁) → (∀𝑖 ∈ (0..^(#‘(𝑊 prefix 𝑀)))((𝑊 prefix 𝑀)‘𝑖) = ((𝑈 prefix 𝑁)‘𝑖) ↔ ∀𝑖 ∈ (0..^𝑀)(𝑊‘𝑖) = (𝑈‘𝑖)))
56	55	pm5.32da 673	. 2 ⊢ (((𝑊 ∈ Word 𝑉 ∧ 𝑈 ∈ Word 𝑉) ∧ (𝑀 ∈ ℕ0 ∧ 𝑁 ∈ ℕ0) ∧ (𝑀 ≤ (#‘𝑊) ∧ 𝑁 ≤ (#‘𝑈))) → ((𝑀 = 𝑁 ∧ ∀𝑖 ∈ (0..^(#‘(𝑊 prefix 𝑀)))((𝑊 prefix 𝑀)‘𝑖) = ((𝑈 prefix 𝑁)‘𝑖)) ↔ (𝑀 = 𝑁 ∧ ∀𝑖 ∈ (0..^𝑀)(𝑊‘𝑖) = (𝑈‘𝑖))))
57	6, 34, 56	3bitrd 294	1 ⊢ (((𝑊 ∈ Word 𝑉 ∧ 𝑈 ∈ Word 𝑉) ∧ (𝑀 ∈ ℕ0 ∧ 𝑁 ∈ ℕ0) ∧ (𝑀 ≤ (#‘𝑊) ∧ 𝑁 ≤ (#‘𝑈))) → ((𝑊 prefix 𝑀) = (𝑈 prefix 𝑁) ↔ (𝑀 = 𝑁 ∧ ∀𝑖 ∈ (0..^𝑀)(𝑊‘𝑖) = (𝑈‘𝑖))))

Syntax hints:   → wi 4   ↔ wb 196   ∧ wa 384   ∧ w3a 1037   = wceq 1483   ∈ wcel 1990  ∀wral 2912   class class class wbr 4653  ‘cfv 5888  (class class class)co 6650  0cc0 9936   ≤ cle 10075  ℕ₀cn0 11292  ...cfz 12326  ..^cfzo 12465  #chash 13117  Word cword 13291   prefix cpfx 41381

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1722  ax-4 1737  ax-5 1839  ax-6 1888  ax-7 1935  ax-8 1992  ax-9 1999  ax-10 2019  ax-11 2034  ax-12 2047  ax-13 2246  ax-ext 2602  ax-rep 4771  ax-sep 4781  ax-nul 4789  ax-pow 4843  ax-pr 4906  ax-un 6949  ax-cnex 9992  ax-resscn 9993  ax-1cn 9994  ax-icn 9995  ax-addcl 9996  ax-addrcl 9997  ax-mulcl 9998  ax-mulrcl 9999  ax-mulcom 10000  ax-addass 10001  ax-mulass 10002  ax-distr 10003  ax-i2m1 10004  ax-1ne0 10005  ax-1rid 10006  ax-rnegex 10007  ax-rrecex 10008  ax-cnre 10009  ax-pre-lttri 10010  ax-pre-lttrn 10011  ax-pre-ltadd 10012  ax-pre-mulgt0 10013

This theorem depends on definitions:  df-bi 197  df-or 385  df-an 386  df-3or 1038  df-3an 1039  df-tru 1486  df-ex 1705  df-nf 1710  df-sb 1881  df-eu 2474  df-mo 2475  df-clab 2609  df-cleq 2615  df-clel 2618  df-nfc 2753  df-ne 2795  df-nel 2898  df-ral 2917  df-rex 2918  df-reu 2919  df-rab 2921  df-v 3202  df-sbc 3436  df-csb 3534  df-dif 3577  df-un 3579  df-in 3581  df-ss 3588  df-pss 3590  df-nul 3916  df-if 4087  df-pw 4160  df-sn 4178  df-pr 4180  df-tp 4182  df-op 4184  df-uni 4437  df-int 4476  df-iun 4522  df-br 4654  df-opab 4713  df-mpt 4730  df-tr 4753  df-id 5024  df-eprel 5029  df-po 5035  df-so 5036  df-fr 5073  df-we 5075  df-xp 5120  df-rel 5121  df-cnv 5122  df-co 5123  df-dm 5124  df-rn 5125  df-res 5126  df-ima 5127  df-pred 5680  df-ord 5726  df-on 5727  df-lim 5728  df-suc 5729  df-iota 5851  df-fun 5890  df-fn 5891  df-f 5892  df-f1 5893  df-fo 5894  df-f1o 5895  df-fv 5896  df-riota 6611  df-ov 6653  df-oprab 6654  df-mpt2 6655  df-om 7066  df-1st 7168  df-2nd 7169  df-wrecs 7407  df-recs 7468  df-rdg 7506  df-1o 7560  df-oadd 7564  df-er 7742  df-en 7956  df-dom 7957  df-sdom 7958  df-fin 7959  df-card 8765  df-pnf 10076  df-mnf 10077  df-xr 10078  df-ltxr 10079  df-le 10080  df-sub 10268  df-neg 10269  df-nn 11021  df-n0 11293  df-z 11378  df-uz 11688  df-fz 12327  df-fzo 12466  df-hash 13118  df-word 13299  df-substr 13303  df-pfx 41382

This theorem is referenced by:  pfxsuffeqwrdeq  41406