Metamath Proof Explorer


Theorem dffr5

Description: A quantifier-free definition of a well-founded relationship. (Contributed by Scott Fenton, 11-Apr-2011)

Ref Expression
Assertion dffr5 R Fr A 𝒫 A ran E E R -1

Proof

Step Hyp Ref Expression
1 eldif x 𝒫 A x 𝒫 A ¬ x
2 velpw x 𝒫 A x A
3 velsn x x =
4 3 necon3bbii ¬ x x
5 2 4 anbi12i x 𝒫 A ¬ x x A x
6 1 5 bitri x 𝒫 A x A x
7 brdif y E E R -1 x y E x ¬ y E R -1 x
8 epel y E x y x
9 vex y V
10 vex x V
11 9 10 coep y E R -1 x z x y R -1 z
12 vex z V
13 9 12 brcnv y R -1 z z R y
14 13 rexbii z x y R -1 z z x z R y
15 dfrex2 z x z R y ¬ z x ¬ z R y
16 11 14 15 3bitrri ¬ z x ¬ z R y y E R -1 x
17 16 con1bii ¬ y E R -1 x z x ¬ z R y
18 8 17 anbi12i y E x ¬ y E R -1 x y x z x ¬ z R y
19 7 18 bitri y E E R -1 x y x z x ¬ z R y
20 19 exbii y y E E R -1 x y y x z x ¬ z R y
21 10 elrn x ran E E R -1 y y E E R -1 x
22 df-rex y x z x ¬ z R y y y x z x ¬ z R y
23 20 21 22 3bitr4i x ran E E R -1 y x z x ¬ z R y
24 6 23 imbi12i x 𝒫 A x ran E E R -1 x A x y x z x ¬ z R y
25 24 albii x x 𝒫 A x ran E E R -1 x x A x y x z x ¬ z R y
26 dfss2 𝒫 A ran E E R -1 x x 𝒫 A x ran E E R -1
27 df-fr R Fr A x x A x y x z x ¬ z R y
28 25 26 27 3bitr4ri R Fr A 𝒫 A ran E E R -1