Metamath Proof Explorer


Theorem efgi2

Description: Value of the free group construction. (Contributed by Mario Carneiro, 1-Oct-2015)

Ref Expression
Hypotheses efgval.w W = I Word I × 2 𝑜
efgval.r ˙ = ~ FG I
efgval2.m M = y I , z 2 𝑜 y 1 𝑜 z
efgval2.t T = v W n 0 v , w I × 2 𝑜 v splice n n ⟨“ w M w ”⟩
Assertion efgi2 A W B ran T A A ˙ B

Proof

Step Hyp Ref Expression
1 efgval.w W = I Word I × 2 𝑜
2 efgval.r ˙ = ~ FG I
3 efgval2.m M = y I , z 2 𝑜 y 1 𝑜 z
4 efgval2.t T = v W n 0 v , w I × 2 𝑜 v splice n n ⟨“ w M w ”⟩
5 fveq2 a = A T a = T A
6 5 rneqd a = A ran T a = ran T A
7 eceq1 a = A a r = A r
8 6 7 sseq12d a = A ran T a a r ran T A A r
9 8 rspcv A W a W ran T a a r ran T A A r
10 9 adantr A W B ran T A a W ran T a a r ran T A A r
11 ssel ran T A A r B ran T A B A r
12 11 com12 B ran T A ran T A A r B A r
13 simpl B A r A W B A r
14 elecg B A r A W B A r A r B
15 13 14 mpbid B A r A W A r B
16 df-br A r B A B r
17 15 16 sylib B A r A W A B r
18 17 expcom A W B A r A B r
19 12 18 sylan9r A W B ran T A ran T A A r A B r
20 10 19 syld A W B ran T A a W ran T a a r A B r
21 20 adantld A W B ran T A r Er W a W ran T a a r A B r
22 21 alrimiv A W B ran T A r r Er W a W ran T a a r A B r
23 opex A B V
24 23 elintab A B r | r Er W a W ran T a a r r r Er W a W ran T a a r A B r
25 22 24 sylibr A W B ran T A A B r | r Er W a W ran T a a r
26 1 2 3 4 efgval2 ˙ = r | r Er W a W ran T a a r
27 25 26 eleqtrrdi A W B ran T A A B ˙
28 df-br A ˙ B A B ˙
29 27 28 sylibr A W B ran T A A ˙ B