| Step | Hyp | Ref | Expression | 
|---|
| 1 |  | 1onn 8679 | . . . . . . . 8
⊢
1o ∈ ω | 
| 2 |  | 1n0 8527 | . . . . . . . 8
⊢
1o ≠ ∅ | 
| 3 |  | eldifsn 4785 | . . . . . . . 8
⊢
(1o ∈ (ω ∖ {∅}) ↔ (1o
∈ ω ∧ 1o ≠ ∅)) | 
| 4 | 1, 2, 3 | mpbir2an 711 | . . . . . . 7
⊢
1o ∈ (ω ∖ {∅}) | 
| 5 | 4 | ne0ii 4343 | . . . . . 6
⊢ (ω
∖ {∅}) ≠ ∅ | 
| 6 |  | biid 261 | . . . . . . 7
⊢ ((𝑓‘∅) = pred(𝑋, 𝐴, 𝑅) ↔ (𝑓‘∅) = pred(𝑋, 𝐴, 𝑅)) | 
| 7 |  | biid 261 | . . . . . . 7
⊢
(∀𝑖 ∈
ω (suc 𝑖 ∈ 𝑛 → (𝑓‘suc 𝑖) = ∪ 𝑦 ∈ (𝑓‘𝑖) pred(𝑦, 𝐴, 𝑅)) ↔ ∀𝑖 ∈ ω (suc 𝑖 ∈ 𝑛 → (𝑓‘suc 𝑖) = ∪ 𝑦 ∈ (𝑓‘𝑖) pred(𝑦, 𝐴, 𝑅))) | 
| 8 |  | eqid 2736 | . . . . . . 7
⊢ (ω
∖ {∅}) = (ω ∖ {∅}) | 
| 9 | 6, 7, 8 | bnj852 34936 | . . . . . 6
⊢ ((𝑅 FrSe 𝐴 ∧ 𝑋 ∈ 𝐴) → ∀𝑛 ∈ (ω ∖
{∅})∃!𝑓(𝑓 Fn 𝑛 ∧ (𝑓‘∅) = pred(𝑋, 𝐴, 𝑅) ∧ ∀𝑖 ∈ ω (suc 𝑖 ∈ 𝑛 → (𝑓‘suc 𝑖) = ∪ 𝑦 ∈ (𝑓‘𝑖) pred(𝑦, 𝐴, 𝑅)))) | 
| 10 |  | r19.2z 4494 | . . . . . 6
⊢
(((ω ∖ {∅}) ≠ ∅ ∧ ∀𝑛 ∈ (ω ∖
{∅})∃!𝑓(𝑓 Fn 𝑛 ∧ (𝑓‘∅) = pred(𝑋, 𝐴, 𝑅) ∧ ∀𝑖 ∈ ω (suc 𝑖 ∈ 𝑛 → (𝑓‘suc 𝑖) = ∪ 𝑦 ∈ (𝑓‘𝑖) pred(𝑦, 𝐴, 𝑅)))) → ∃𝑛 ∈ (ω ∖
{∅})∃!𝑓(𝑓 Fn 𝑛 ∧ (𝑓‘∅) = pred(𝑋, 𝐴, 𝑅) ∧ ∀𝑖 ∈ ω (suc 𝑖 ∈ 𝑛 → (𝑓‘suc 𝑖) = ∪ 𝑦 ∈ (𝑓‘𝑖) pred(𝑦, 𝐴, 𝑅)))) | 
| 11 | 5, 9, 10 | sylancr 587 | . . . . 5
⊢ ((𝑅 FrSe 𝐴 ∧ 𝑋 ∈ 𝐴) → ∃𝑛 ∈ (ω ∖
{∅})∃!𝑓(𝑓 Fn 𝑛 ∧ (𝑓‘∅) = pred(𝑋, 𝐴, 𝑅) ∧ ∀𝑖 ∈ ω (suc 𝑖 ∈ 𝑛 → (𝑓‘suc 𝑖) = ∪ 𝑦 ∈ (𝑓‘𝑖) pred(𝑦, 𝐴, 𝑅)))) | 
| 12 |  | euex 2576 | . . . . 5
⊢
(∃!𝑓(𝑓 Fn 𝑛 ∧ (𝑓‘∅) = pred(𝑋, 𝐴, 𝑅) ∧ ∀𝑖 ∈ ω (suc 𝑖 ∈ 𝑛 → (𝑓‘suc 𝑖) = ∪ 𝑦 ∈ (𝑓‘𝑖) pred(𝑦, 𝐴, 𝑅))) → ∃𝑓(𝑓 Fn 𝑛 ∧ (𝑓‘∅) = pred(𝑋, 𝐴, 𝑅) ∧ ∀𝑖 ∈ ω (suc 𝑖 ∈ 𝑛 → (𝑓‘suc 𝑖) = ∪ 𝑦 ∈ (𝑓‘𝑖) pred(𝑦, 𝐴, 𝑅)))) | 
| 13 | 11, 12 | bnj31 34734 | . . . 4
⊢ ((𝑅 FrSe 𝐴 ∧ 𝑋 ∈ 𝐴) → ∃𝑛 ∈ (ω ∖
{∅})∃𝑓(𝑓 Fn 𝑛 ∧ (𝑓‘∅) = pred(𝑋, 𝐴, 𝑅) ∧ ∀𝑖 ∈ ω (suc 𝑖 ∈ 𝑛 → (𝑓‘suc 𝑖) = ∪ 𝑦 ∈ (𝑓‘𝑖) pred(𝑦, 𝐴, 𝑅)))) | 
| 14 |  | rexcom4 3287 | . . . 4
⊢
(∃𝑛 ∈
(ω ∖ {∅})∃𝑓(𝑓 Fn 𝑛 ∧ (𝑓‘∅) = pred(𝑋, 𝐴, 𝑅) ∧ ∀𝑖 ∈ ω (suc 𝑖 ∈ 𝑛 → (𝑓‘suc 𝑖) = ∪ 𝑦 ∈ (𝑓‘𝑖) pred(𝑦, 𝐴, 𝑅))) ↔ ∃𝑓∃𝑛 ∈ (ω ∖ {∅})(𝑓 Fn 𝑛 ∧ (𝑓‘∅) = pred(𝑋, 𝐴, 𝑅) ∧ ∀𝑖 ∈ ω (suc 𝑖 ∈ 𝑛 → (𝑓‘suc 𝑖) = ∪ 𝑦 ∈ (𝑓‘𝑖) pred(𝑦, 𝐴, 𝑅)))) | 
| 15 | 13, 14 | sylib 218 | . . 3
⊢ ((𝑅 FrSe 𝐴 ∧ 𝑋 ∈ 𝐴) → ∃𝑓∃𝑛 ∈ (ω ∖ {∅})(𝑓 Fn 𝑛 ∧ (𝑓‘∅) = pred(𝑋, 𝐴, 𝑅) ∧ ∀𝑖 ∈ ω (suc 𝑖 ∈ 𝑛 → (𝑓‘suc 𝑖) = ∪ 𝑦 ∈ (𝑓‘𝑖) pred(𝑦, 𝐴, 𝑅)))) | 
| 16 |  | abid 2717 | . . 3
⊢ (𝑓 ∈ {𝑓 ∣ ∃𝑛 ∈ (ω ∖ {∅})(𝑓 Fn 𝑛 ∧ (𝑓‘∅) = pred(𝑋, 𝐴, 𝑅) ∧ ∀𝑖 ∈ ω (suc 𝑖 ∈ 𝑛 → (𝑓‘suc 𝑖) = ∪ 𝑦 ∈ (𝑓‘𝑖) pred(𝑦, 𝐴, 𝑅)))} ↔ ∃𝑛 ∈ (ω ∖ {∅})(𝑓 Fn 𝑛 ∧ (𝑓‘∅) = pred(𝑋, 𝐴, 𝑅) ∧ ∀𝑖 ∈ ω (suc 𝑖 ∈ 𝑛 → (𝑓‘suc 𝑖) = ∪ 𝑦 ∈ (𝑓‘𝑖) pred(𝑦, 𝐴, 𝑅)))) | 
| 17 | 15, 16 | bnj1198 34810 | . 2
⊢ ((𝑅 FrSe 𝐴 ∧ 𝑋 ∈ 𝐴) → ∃𝑓 𝑓 ∈ {𝑓 ∣ ∃𝑛 ∈ (ω ∖ {∅})(𝑓 Fn 𝑛 ∧ (𝑓‘∅) = pred(𝑋, 𝐴, 𝑅) ∧ ∀𝑖 ∈ ω (suc 𝑖 ∈ 𝑛 → (𝑓‘suc 𝑖) = ∪ 𝑦 ∈ (𝑓‘𝑖) pred(𝑦, 𝐴, 𝑅)))}) | 
| 18 |  | simp2 1137 | . . . . . . 7
⊢ ((𝑓 Fn 𝑛 ∧ (𝑓‘∅) = pred(𝑋, 𝐴, 𝑅) ∧ ∀𝑖 ∈ ω (suc 𝑖 ∈ 𝑛 → (𝑓‘suc 𝑖) = ∪ 𝑦 ∈ (𝑓‘𝑖) pred(𝑦, 𝐴, 𝑅))) → (𝑓‘∅) = pred(𝑋, 𝐴, 𝑅)) | 
| 19 | 18 | reximi 3083 | . . . . . 6
⊢
(∃𝑛 ∈
(ω ∖ {∅})(𝑓 Fn 𝑛 ∧ (𝑓‘∅) = pred(𝑋, 𝐴, 𝑅) ∧ ∀𝑖 ∈ ω (suc 𝑖 ∈ 𝑛 → (𝑓‘suc 𝑖) = ∪ 𝑦 ∈ (𝑓‘𝑖) pred(𝑦, 𝐴, 𝑅))) → ∃𝑛 ∈ (ω ∖ {∅})(𝑓‘∅) = pred(𝑋, 𝐴, 𝑅)) | 
| 20 | 16, 19 | sylbi 217 | . . . . 5
⊢ (𝑓 ∈ {𝑓 ∣ ∃𝑛 ∈ (ω ∖ {∅})(𝑓 Fn 𝑛 ∧ (𝑓‘∅) = pred(𝑋, 𝐴, 𝑅) ∧ ∀𝑖 ∈ ω (suc 𝑖 ∈ 𝑛 → (𝑓‘suc 𝑖) = ∪ 𝑦 ∈ (𝑓‘𝑖) pred(𝑦, 𝐴, 𝑅)))} → ∃𝑛 ∈ (ω ∖ {∅})(𝑓‘∅) = pred(𝑋, 𝐴, 𝑅)) | 
| 21 |  | df-rex 3070 | . . . . . 6
⊢
(∃𝑛 ∈
(ω ∖ {∅})(𝑓‘∅) = pred(𝑋, 𝐴, 𝑅) ↔ ∃𝑛(𝑛 ∈ (ω ∖ {∅}) ∧
(𝑓‘∅) =
pred(𝑋, 𝐴, 𝑅))) | 
| 22 |  | 19.41v 1948 | . . . . . . 7
⊢
(∃𝑛(𝑛 ∈ (ω ∖
{∅}) ∧ (𝑓‘∅) = pred(𝑋, 𝐴, 𝑅)) ↔ (∃𝑛 𝑛 ∈ (ω ∖ {∅}) ∧
(𝑓‘∅) =
pred(𝑋, 𝐴, 𝑅))) | 
| 23 | 22 | simprbi 496 | . . . . . 6
⊢
(∃𝑛(𝑛 ∈ (ω ∖
{∅}) ∧ (𝑓‘∅) = pred(𝑋, 𝐴, 𝑅)) → (𝑓‘∅) = pred(𝑋, 𝐴, 𝑅)) | 
| 24 | 21, 23 | sylbi 217 | . . . . 5
⊢
(∃𝑛 ∈
(ω ∖ {∅})(𝑓‘∅) = pred(𝑋, 𝐴, 𝑅) → (𝑓‘∅) = pred(𝑋, 𝐴, 𝑅)) | 
| 25 | 20, 24 | syl 17 | . . . 4
⊢ (𝑓 ∈ {𝑓 ∣ ∃𝑛 ∈ (ω ∖ {∅})(𝑓 Fn 𝑛 ∧ (𝑓‘∅) = pred(𝑋, 𝐴, 𝑅) ∧ ∀𝑖 ∈ ω (suc 𝑖 ∈ 𝑛 → (𝑓‘suc 𝑖) = ∪ 𝑦 ∈ (𝑓‘𝑖) pred(𝑦, 𝐴, 𝑅)))} → (𝑓‘∅) = pred(𝑋, 𝐴, 𝑅)) | 
| 26 |  | eqid 2736 | . . . . . . 7
⊢ {𝑓 ∣ ∃𝑛 ∈ (ω ∖
{∅})(𝑓 Fn 𝑛 ∧ (𝑓‘∅) = pred(𝑋, 𝐴, 𝑅) ∧ ∀𝑖 ∈ ω (suc 𝑖 ∈ 𝑛 → (𝑓‘suc 𝑖) = ∪ 𝑦 ∈ (𝑓‘𝑖) pred(𝑦, 𝐴, 𝑅)))} = {𝑓 ∣ ∃𝑛 ∈ (ω ∖ {∅})(𝑓 Fn 𝑛 ∧ (𝑓‘∅) = pred(𝑋, 𝐴, 𝑅) ∧ ∀𝑖 ∈ ω (suc 𝑖 ∈ 𝑛 → (𝑓‘suc 𝑖) = ∪ 𝑦 ∈ (𝑓‘𝑖) pred(𝑦, 𝐴, 𝑅)))} | 
| 27 | 8, 26 | bnj900 34944 | . . . . . 6
⊢ (𝑓 ∈ {𝑓 ∣ ∃𝑛 ∈ (ω ∖ {∅})(𝑓 Fn 𝑛 ∧ (𝑓‘∅) = pred(𝑋, 𝐴, 𝑅) ∧ ∀𝑖 ∈ ω (suc 𝑖 ∈ 𝑛 → (𝑓‘suc 𝑖) = ∪ 𝑦 ∈ (𝑓‘𝑖) pred(𝑦, 𝐴, 𝑅)))} → ∅ ∈ dom 𝑓) | 
| 28 |  | fveq2 6905 | . . . . . . 7
⊢ (𝑖 = ∅ → (𝑓‘𝑖) = (𝑓‘∅)) | 
| 29 | 28 | ssiun2s 5047 | . . . . . 6
⊢ (∅
∈ dom 𝑓 → (𝑓‘∅) ⊆ ∪ 𝑖 ∈ dom 𝑓(𝑓‘𝑖)) | 
| 30 | 27, 29 | syl 17 | . . . . 5
⊢ (𝑓 ∈ {𝑓 ∣ ∃𝑛 ∈ (ω ∖ {∅})(𝑓 Fn 𝑛 ∧ (𝑓‘∅) = pred(𝑋, 𝐴, 𝑅) ∧ ∀𝑖 ∈ ω (suc 𝑖 ∈ 𝑛 → (𝑓‘suc 𝑖) = ∪ 𝑦 ∈ (𝑓‘𝑖) pred(𝑦, 𝐴, 𝑅)))} → (𝑓‘∅) ⊆ ∪ 𝑖 ∈ dom 𝑓(𝑓‘𝑖)) | 
| 31 |  | ssiun2 5046 | . . . . . 6
⊢ (𝑓 ∈ {𝑓 ∣ ∃𝑛 ∈ (ω ∖ {∅})(𝑓 Fn 𝑛 ∧ (𝑓‘∅) = pred(𝑋, 𝐴, 𝑅) ∧ ∀𝑖 ∈ ω (suc 𝑖 ∈ 𝑛 → (𝑓‘suc 𝑖) = ∪ 𝑦 ∈ (𝑓‘𝑖) pred(𝑦, 𝐴, 𝑅)))} → ∪ 𝑖 ∈ dom 𝑓(𝑓‘𝑖) ⊆ ∪
𝑓 ∈ {𝑓 ∣ ∃𝑛 ∈ (ω ∖
{∅})(𝑓 Fn 𝑛 ∧ (𝑓‘∅) = pred(𝑋, 𝐴, 𝑅) ∧ ∀𝑖 ∈ ω (suc 𝑖 ∈ 𝑛 → (𝑓‘suc 𝑖) = ∪ 𝑦 ∈ (𝑓‘𝑖) pred(𝑦, 𝐴, 𝑅)))}∪
𝑖 ∈ dom 𝑓(𝑓‘𝑖)) | 
| 32 | 6, 7, 8, 26 | bnj882 34941 | . . . . . 6
⊢ 
trCl(𝑋, 𝐴, 𝑅) = ∪
𝑓 ∈ {𝑓 ∣ ∃𝑛 ∈ (ω ∖
{∅})(𝑓 Fn 𝑛 ∧ (𝑓‘∅) = pred(𝑋, 𝐴, 𝑅) ∧ ∀𝑖 ∈ ω (suc 𝑖 ∈ 𝑛 → (𝑓‘suc 𝑖) = ∪ 𝑦 ∈ (𝑓‘𝑖) pred(𝑦, 𝐴, 𝑅)))}∪
𝑖 ∈ dom 𝑓(𝑓‘𝑖) | 
| 33 | 31, 32 | sseqtrrdi 4024 | . . . . 5
⊢ (𝑓 ∈ {𝑓 ∣ ∃𝑛 ∈ (ω ∖ {∅})(𝑓 Fn 𝑛 ∧ (𝑓‘∅) = pred(𝑋, 𝐴, 𝑅) ∧ ∀𝑖 ∈ ω (suc 𝑖 ∈ 𝑛 → (𝑓‘suc 𝑖) = ∪ 𝑦 ∈ (𝑓‘𝑖) pred(𝑦, 𝐴, 𝑅)))} → ∪ 𝑖 ∈ dom 𝑓(𝑓‘𝑖) ⊆ trCl(𝑋, 𝐴, 𝑅)) | 
| 34 | 30, 33 | sstrd 3993 | . . . 4
⊢ (𝑓 ∈ {𝑓 ∣ ∃𝑛 ∈ (ω ∖ {∅})(𝑓 Fn 𝑛 ∧ (𝑓‘∅) = pred(𝑋, 𝐴, 𝑅) ∧ ∀𝑖 ∈ ω (suc 𝑖 ∈ 𝑛 → (𝑓‘suc 𝑖) = ∪ 𝑦 ∈ (𝑓‘𝑖) pred(𝑦, 𝐴, 𝑅)))} → (𝑓‘∅) ⊆ trCl(𝑋, 𝐴, 𝑅)) | 
| 35 | 25, 34 | eqsstrrd 4018 | . . 3
⊢ (𝑓 ∈ {𝑓 ∣ ∃𝑛 ∈ (ω ∖ {∅})(𝑓 Fn 𝑛 ∧ (𝑓‘∅) = pred(𝑋, 𝐴, 𝑅) ∧ ∀𝑖 ∈ ω (suc 𝑖 ∈ 𝑛 → (𝑓‘suc 𝑖) = ∪ 𝑦 ∈ (𝑓‘𝑖) pred(𝑦, 𝐴, 𝑅)))} → pred(𝑋, 𝐴, 𝑅) ⊆ trCl(𝑋, 𝐴, 𝑅)) | 
| 36 | 35 | exlimiv 1929 | . 2
⊢
(∃𝑓 𝑓 ∈ {𝑓 ∣ ∃𝑛 ∈ (ω ∖ {∅})(𝑓 Fn 𝑛 ∧ (𝑓‘∅) = pred(𝑋, 𝐴, 𝑅) ∧ ∀𝑖 ∈ ω (suc 𝑖 ∈ 𝑛 → (𝑓‘suc 𝑖) = ∪ 𝑦 ∈ (𝑓‘𝑖) pred(𝑦, 𝐴, 𝑅)))} → pred(𝑋, 𝐴, 𝑅) ⊆ trCl(𝑋, 𝐴, 𝑅)) | 
| 37 | 17, 36 | syl 17 | 1
⊢ ((𝑅 FrSe 𝐴 ∧ 𝑋 ∈ 𝐴) → pred(𝑋, 𝐴, 𝑅) ⊆ trCl(𝑋, 𝐴, 𝑅)) |