Metamath Proof Explorer


Theorem efgcpbl2

Description: Two extension sequences have related endpoints iff they have the same base. (Contributed by Mario Carneiro, 1-Oct-2015)

Ref Expression
Hypotheses efgval.w W=IWordI×2𝑜
efgval.r ˙=~FGI
efgval2.m M=yI,z2𝑜y1𝑜z
efgval2.t T=vWn0v,wI×2𝑜vsplicenn⟨“wMw”⟩
efgred.d D=WxWranTx
efgred.s S=mtWordW|t0Dk1..^ttkranTtk1mm1
Assertion efgcpbl2 A˙XB˙YA++B˙X++Y

Proof

Step Hyp Ref Expression
1 efgval.w W=IWordI×2𝑜
2 efgval.r ˙=~FGI
3 efgval2.m M=yI,z2𝑜y1𝑜z
4 efgval2.t T=vWn0v,wI×2𝑜vsplicenn⟨“wMw”⟩
5 efgred.d D=WxWranTx
6 efgred.s S=mtWordW|t0Dk1..^ttkranTtk1mm1
7 1 2 efger ˙ErW
8 7 a1i A˙XB˙Y˙ErW
9 simpl A˙XB˙YA˙X
10 8 9 ercl A˙XB˙YAW
11 wrd0 WordI×2𝑜
12 1 efgrcl AWIVW=WordI×2𝑜
13 10 12 syl A˙XB˙YIVW=WordI×2𝑜
14 13 simprd A˙XB˙YW=WordI×2𝑜
15 11 14 eleqtrrid A˙XB˙YW
16 simpr A˙XB˙YB˙Y
17 1 2 3 4 5 6 efgcpbl AWWB˙YA++B++˙A++Y++
18 10 15 16 17 syl3anc A˙XB˙YA++B++˙A++Y++
19 10 14 eleqtrd A˙XB˙YAWordI×2𝑜
20 8 16 ercl A˙XB˙YBW
21 20 14 eleqtrd A˙XB˙YBWordI×2𝑜
22 ccatcl AWordI×2𝑜BWordI×2𝑜A++BWordI×2𝑜
23 19 21 22 syl2anc A˙XB˙YA++BWordI×2𝑜
24 ccatrid A++BWordI×2𝑜A++B++=A++B
25 23 24 syl A˙XB˙YA++B++=A++B
26 8 16 ercl2 A˙XB˙YYW
27 26 14 eleqtrd A˙XB˙YYWordI×2𝑜
28 ccatcl AWordI×2𝑜YWordI×2𝑜A++YWordI×2𝑜
29 19 27 28 syl2anc A˙XB˙YA++YWordI×2𝑜
30 ccatrid A++YWordI×2𝑜A++Y++=A++Y
31 29 30 syl A˙XB˙YA++Y++=A++Y
32 18 25 31 3brtr3d A˙XB˙YA++B˙A++Y
33 1 2 3 4 5 6 efgcpbl WYWA˙X++A++Y˙++X++Y
34 15 26 9 33 syl3anc A˙XB˙Y++A++Y˙++X++Y
35 ccatlid AWordI×2𝑜++A=A
36 19 35 syl A˙XB˙Y++A=A
37 36 oveq1d A˙XB˙Y++A++Y=A++Y
38 8 9 ercl2 A˙XB˙YXW
39 38 14 eleqtrd A˙XB˙YXWordI×2𝑜
40 ccatlid XWordI×2𝑜++X=X
41 39 40 syl A˙XB˙Y++X=X
42 41 oveq1d A˙XB˙Y++X++Y=X++Y
43 34 37 42 3brtr3d A˙XB˙YA++Y˙X++Y
44 8 32 43 ertrd A˙XB˙YA++B˙X++Y