Metamath Proof Explorer


Theorem clsk1indlem3

Description: The ansatz closure function ( r e. ~P 3o |-> if ( r = { (/) } , { (/) , 1o } , r ) ) has the K3 property of being sub-linear. (Contributed by RP, 6-Jul-2021)

Ref Expression
Hypothesis clsk1indlem.k ⊢ K = r ∈ 𝒫 3 𝑜 ⟼ if r = ∅ ∅ 1 𝑜 r
Assertion clsk1indlem3 ⊢ ∀ s ∈ 𝒫 3 𝑜 ∀ t ∈ 𝒫 3 𝑜 K ⁡ s ∪ t ⊆ K ⁡ s ∪ K ⁡ t

Proof

Step Hyp Ref Expression
1 clsk1indlem.k ⊢ K = r ∈ 𝒫 3 𝑜 ⟼ if r = ∅ ∅ 1 𝑜 r
2 elif ⊢ x ∈ if s ∪ t = ∅ ∅ 1 𝑜 s ∪ t ↔ s ∪ t = ∅ ∧ x ∈ ∅ 1 𝑜 ∨ ¬ s ∪ t = ∅ ∧ x ∈ s ∪ t
3 uneq12 ⊢ s = ∅ ∧ t = ∅ → s ∪ t = ∅ ∪ ∅
4 unidm ⊢ ∅ ∪ ∅ = ∅
5 3 4 eqtrdi ⊢ s = ∅ ∧ t = ∅ → s ∪ t = ∅
6 an3 ⊢ s = ∅ ∧ t = ∅ ∧ s ∪ t = ∅ ∧ x ∈ ∅ 1 𝑜 → s = ∅ ∧ x ∈ ∅ 1 𝑜
7 6 orcd ⊢ s = ∅ ∧ t = ∅ ∧ s ∪ t = ∅ ∧ x ∈ ∅ 1 𝑜 → s = ∅ ∧ x ∈ ∅ 1 𝑜 ∨ ¬ s = ∅ ∧ x ∈ s
8 7 orcd ⊢ s = ∅ ∧ t = ∅ ∧ s ∪ t = ∅ ∧ x ∈ ∅ 1 𝑜 → s = ∅ ∧ x ∈ ∅ 1 𝑜 ∨ ¬ s = ∅ ∧ x ∈ s ∨ t = ∅ ∧ x ∈ ∅ 1 𝑜 ∨ ¬ t = ∅ ∧ x ∈ t
9 8 ex ⊢ s = ∅ ∧ t = ∅ → s ∪ t = ∅ ∧ x ∈ ∅ 1 𝑜 → s = ∅ ∧ x ∈ ∅ 1 𝑜 ∨ ¬ s = ∅ ∧ x ∈ s ∨ t = ∅ ∧ x ∈ ∅ 1 𝑜 ∨ ¬ t = ∅ ∧ x ∈ t
10 pm2.24 ⊢ s ∪ t = ∅ → ¬ s ∪ t = ∅ → x ∈ s ∪ t → s = ∅ ∧ x ∈ ∅ 1 𝑜 ∨ ¬ s = ∅ ∧ x ∈ s ∨ t = ∅ ∧ x ∈ ∅ 1 𝑜 ∨ ¬ t = ∅ ∧ x ∈ t
11 10 impd ⊢ s ∪ t = ∅ → ¬ s ∪ t = ∅ ∧ x ∈ s ∪ t → s = ∅ ∧ x ∈ ∅ 1 𝑜 ∨ ¬ s = ∅ ∧ x ∈ s ∨ t = ∅ ∧ x ∈ ∅ 1 𝑜 ∨ ¬ t = ∅ ∧ x ∈ t
12 9 11 jaao ⊢ s = ∅ ∧ t = ∅ ∧ s ∪ t = ∅ → s ∪ t = ∅ ∧ x ∈ ∅ 1 𝑜 ∨ ¬ s ∪ t = ∅ ∧ x ∈ s ∪ t → s = ∅ ∧ x ∈ ∅ 1 𝑜 ∨ ¬ s = ∅ ∧ x ∈ s ∨ t = ∅ ∧ x ∈ ∅ 1 𝑜 ∨ ¬ t = ∅ ∧ x ∈ t
13 5 12 mpdan ⊢ s = ∅ ∧ t = ∅ → s ∪ t = ∅ ∧ x ∈ ∅ 1 𝑜 ∨ ¬ s ∪ t = ∅ ∧ x ∈ s ∪ t → s = ∅ ∧ x ∈ ∅ 1 𝑜 ∨ ¬ s = ∅ ∧ x ∈ s ∨ t = ∅ ∧ x ∈ ∅ 1 𝑜 ∨ ¬ t = ∅ ∧ x ∈ t
14 13 a1i ⊢ s ∈ 𝒫 3 𝑜 ∧ t ∈ 𝒫 3 𝑜 → s = ∅ ∧ t = ∅ → s ∪ t = ∅ ∧ x ∈ ∅ 1 𝑜 ∨ ¬ s ∪ t = ∅ ∧ x ∈ s ∪ t → s = ∅ ∧ x ∈ ∅ 1 𝑜 ∨ ¬ s = ∅ ∧ x ∈ s ∨ t = ∅ ∧ x ∈ ∅ 1 𝑜 ∨ ¬ t = ∅ ∧ x ∈ t
15 uneqsn ⊢ s ∪ t = ∅ ↔ s = ∅ ∧ t = ∅ ∨ s = ∅ ∧ t = ∅ ∨ s = ∅ ∧ t = ∅
16 df-3or ⊢ s = ∅ ∧ t = ∅ ∨ s = ∅ ∧ t = ∅ ∨ s = ∅ ∧ t = ∅ ↔ s = ∅ ∧ t = ∅ ∨ s = ∅ ∧ t = ∅ ∨ s = ∅ ∧ t = ∅
17 15 16 bitri ⊢ s ∪ t = ∅ ↔ s = ∅ ∧ t = ∅ ∨ s = ∅ ∧ t = ∅ ∨ s = ∅ ∧ t = ∅
18 pm2.21 ⊢ ¬ s = ∅ → s = ∅ → x ∈ ∅ 1 𝑜 → s = ∅ ∧ x ∈ ∅ 1 𝑜 ∨ ¬ s = ∅ ∧ x ∈ s ∨ t = ∅ ∧ x ∈ ∅ 1 𝑜 ∨ ¬ t = ∅ ∧ x ∈ t
19 18 adantrd ⊢ ¬ s = ∅ → s = ∅ ∧ t = ∅ → x ∈ ∅ 1 𝑜 → s = ∅ ∧ x ∈ ∅ 1 𝑜 ∨ ¬ s = ∅ ∧ x ∈ s ∨ t = ∅ ∧ x ∈ ∅ 1 𝑜 ∨ ¬ t = ∅ ∧ x ∈ t
20 18 adantrd ⊢ ¬ s = ∅ → s = ∅ ∧ t = ∅ → x ∈ ∅ 1 𝑜 → s = ∅ ∧ x ∈ ∅ 1 𝑜 ∨ ¬ s = ∅ ∧ x ∈ s ∨ t = ∅ ∧ x ∈ ∅ 1 𝑜 ∨ ¬ t = ∅ ∧ x ∈ t
21 19 20 jaod ⊢ ¬ s = ∅ → s = ∅ ∧ t = ∅ ∨ s = ∅ ∧ t = ∅ → x ∈ ∅ 1 𝑜 → s = ∅ ∧ x ∈ ∅ 1 𝑜 ∨ ¬ s = ∅ ∧ x ∈ s ∨ t = ∅ ∧ x ∈ ∅ 1 𝑜 ∨ ¬ t = ∅ ∧ x ∈ t
22 21 adantr ⊢ ¬ s = ∅ ∧ ¬ t = ∅ → s = ∅ ∧ t = ∅ ∨ s = ∅ ∧ t = ∅ → x ∈ ∅ 1 𝑜 → s = ∅ ∧ x ∈ ∅ 1 𝑜 ∨ ¬ s = ∅ ∧ x ∈ s ∨ t = ∅ ∧ x ∈ ∅ 1 𝑜 ∨ ¬ t = ∅ ∧ x ∈ t
23 pm2.21 ⊢ ¬ t = ∅ → t = ∅ → x ∈ ∅ 1 𝑜 → s = ∅ ∧ x ∈ ∅ 1 𝑜 ∨ ¬ s = ∅ ∧ x ∈ s ∨ t = ∅ ∧ x ∈ ∅ 1 𝑜 ∨ ¬ t = ∅ ∧ x ∈ t
24 23 adantl ⊢ ¬ s = ∅ ∧ ¬ t = ∅ → t = ∅ → x ∈ ∅ 1 𝑜 → s = ∅ ∧ x ∈ ∅ 1 𝑜 ∨ ¬ s = ∅ ∧ x ∈ s ∨ t = ∅ ∧ x ∈ ∅ 1 𝑜 ∨ ¬ t = ∅ ∧ x ∈ t
25 24 adantld ⊢ ¬ s = ∅ ∧ ¬ t = ∅ → s = ∅ ∧ t = ∅ → x ∈ ∅ 1 𝑜 → s = ∅ ∧ x ∈ ∅ 1 𝑜 ∨ ¬ s = ∅ ∧ x ∈ s ∨ t = ∅ ∧ x ∈ ∅ 1 𝑜 ∨ ¬ t = ∅ ∧ x ∈ t
26 22 25 jaod ⊢ ¬ s = ∅ ∧ ¬ t = ∅ → s = ∅ ∧ t = ∅ ∨ s = ∅ ∧ t = ∅ ∨ s = ∅ ∧ t = ∅ → x ∈ ∅ 1 𝑜 → s = ∅ ∧ x ∈ ∅ 1 𝑜 ∨ ¬ s = ∅ ∧ x ∈ s ∨ t = ∅ ∧ x ∈ ∅ 1 𝑜 ∨ ¬ t = ∅ ∧ x ∈ t
27 17 26 biimtrid ⊢ ¬ s = ∅ ∧ ¬ t = ∅ → s ∪ t = ∅ → x ∈ ∅ 1 𝑜 → s = ∅ ∧ x ∈ ∅ 1 𝑜 ∨ ¬ s = ∅ ∧ x ∈ s ∨ t = ∅ ∧ x ∈ ∅ 1 𝑜 ∨ ¬ t = ∅ ∧ x ∈ t
28 27 impd ⊢ ¬ s = ∅ ∧ ¬ t = ∅ → s ∪ t = ∅ ∧ x ∈ ∅ 1 𝑜 → s = ∅ ∧ x ∈ ∅ 1 𝑜 ∨ ¬ s = ∅ ∧ x ∈ s ∨ t = ∅ ∧ x ∈ ∅ 1 𝑜 ∨ ¬ t = ∅ ∧ x ∈ t
29 elun ⊢ x ∈ s ∪ t ↔ x ∈ s ∨ x ∈ t
30 29 bilani ⊢ ¬ s ∪ t = ∅ ∧ x ∈ s ∪ t → x ∈ s ∨ x ∈ t
31 andi ⊢ ¬ s = ∅ ∧ ¬ t = ∅ ∧ x ∈ s ∨ x ∈ t ↔ ¬ s = ∅ ∧ ¬ t = ∅ ∧ x ∈ s ∨ ¬ s = ∅ ∧ ¬ t = ∅ ∧ x ∈ t
32 simpl ⊢ ¬ s = ∅ ∧ ¬ t = ∅ → ¬ s = ∅
33 32 anim1i ⊢ ¬ s = ∅ ∧ ¬ t = ∅ ∧ x ∈ s → ¬ s = ∅ ∧ x ∈ s
34 simpr ⊢ ¬ s = ∅ ∧ ¬ t = ∅ → ¬ t = ∅
35 34 anim1i ⊢ ¬ s = ∅ ∧ ¬ t = ∅ ∧ x ∈ t → ¬ t = ∅ ∧ x ∈ t
36 33 35 orim12i ⊢ ¬ s = ∅ ∧ ¬ t = ∅ ∧ x ∈ s ∨ ¬ s = ∅ ∧ ¬ t = ∅ ∧ x ∈ t → ¬ s = ∅ ∧ x ∈ s ∨ ¬ t = ∅ ∧ x ∈ t
37 31 36 sylbi ⊢ ¬ s = ∅ ∧ ¬ t = ∅ ∧ x ∈ s ∨ x ∈ t → ¬ s = ∅ ∧ x ∈ s ∨ ¬ t = ∅ ∧ x ∈ t
38 30 37 sylan2 ⊢ ¬ s = ∅ ∧ ¬ t = ∅ ∧ ¬ s ∪ t = ∅ ∧ x ∈ s ∪ t → ¬ s = ∅ ∧ x ∈ s ∨ ¬ t = ∅ ∧ x ∈ t
39 38 olcd ⊢ ¬ s = ∅ ∧ ¬ t = ∅ ∧ ¬ s ∪ t = ∅ ∧ x ∈ s ∪ t → s = ∅ ∧ x ∈ ∅ 1 𝑜 ∨ t = ∅ ∧ x ∈ ∅ 1 𝑜 ∨ ¬ s = ∅ ∧ x ∈ s ∨ ¬ t = ∅ ∧ x ∈ t
40 or4 ⊢ s = ∅ ∧ x ∈ ∅ 1 𝑜 ∨ t = ∅ ∧ x ∈ ∅ 1 𝑜 ∨ ¬ s = ∅ ∧ x ∈ s ∨ ¬ t = ∅ ∧ x ∈ t ↔ s = ∅ ∧ x ∈ ∅ 1 𝑜 ∨ ¬ s = ∅ ∧ x ∈ s ∨ t = ∅ ∧ x ∈ ∅ 1 𝑜 ∨ ¬ t = ∅ ∧ x ∈ t
41 39 40 sylib ⊢ ¬ s = ∅ ∧ ¬ t = ∅ ∧ ¬ s ∪ t = ∅ ∧ x ∈ s ∪ t → s = ∅ ∧ x ∈ ∅ 1 𝑜 ∨ ¬ s = ∅ ∧ x ∈ s ∨ t = ∅ ∧ x ∈ ∅ 1 𝑜 ∨ ¬ t = ∅ ∧ x ∈ t
42 41 ex ⊢ ¬ s = ∅ ∧ ¬ t = ∅ → ¬ s ∪ t = ∅ ∧ x ∈ s ∪ t → s = ∅ ∧ x ∈ ∅ 1 𝑜 ∨ ¬ s = ∅ ∧ x ∈ s ∨ t = ∅ ∧ x ∈ ∅ 1 𝑜 ∨ ¬ t = ∅ ∧ x ∈ t
43 28 42 jaod ⊢ ¬ s = ∅ ∧ ¬ t = ∅ → s ∪ t = ∅ ∧ x ∈ ∅ 1 𝑜 ∨ ¬ s ∪ t = ∅ ∧ x ∈ s ∪ t → s = ∅ ∧ x ∈ ∅ 1 𝑜 ∨ ¬ s = ∅ ∧ x ∈ s ∨ t = ∅ ∧ x ∈ ∅ 1 𝑜 ∨ ¬ t = ∅ ∧ x ∈ t
44 43 a1i ⊢ s ∈ 𝒫 3 𝑜 ∧ t ∈ 𝒫 3 𝑜 → ¬ s = ∅ ∧ ¬ t = ∅ → s ∪ t = ∅ ∧ x ∈ ∅ 1 𝑜 ∨ ¬ s ∪ t = ∅ ∧ x ∈ s ∪ t → s = ∅ ∧ x ∈ ∅ 1 𝑜 ∨ ¬ s = ∅ ∧ x ∈ s ∨ t = ∅ ∧ x ∈ ∅ 1 𝑜 ∨ ¬ t = ∅ ∧ x ∈ t
45 14 44 jaod ⊢ s ∈ 𝒫 3 𝑜 ∧ t ∈ 𝒫 3 𝑜 → s = ∅ ∧ t = ∅ ∨ ¬ s = ∅ ∧ ¬ t = ∅ → s ∪ t = ∅ ∧ x ∈ ∅ 1 𝑜 ∨ ¬ s ∪ t = ∅ ∧ x ∈ s ∪ t → s = ∅ ∧ x ∈ ∅ 1 𝑜 ∨ ¬ s = ∅ ∧ x ∈ s ∨ t = ∅ ∧ x ∈ ∅ 1 𝑜 ∨ ¬ t = ∅ ∧ x ∈ t
46 orc ⊢ s = ∅ ∧ x ∈ ∅ 1 𝑜 → s = ∅ ∧ x ∈ ∅ 1 𝑜 ∨ ¬ t = ∅ ∧ x ∈ t
47 46 expcom ⊢ x ∈ ∅ 1 𝑜 → s = ∅ → s = ∅ ∧ x ∈ ∅ 1 𝑜 ∨ ¬ t = ∅ ∧ x ∈ t
48 47 adantrd ⊢ x ∈ ∅ 1 𝑜 → s = ∅ ∧ ¬ t = ∅ → s = ∅ ∧ x ∈ ∅ 1 𝑜 ∨ ¬ t = ∅ ∧ x ∈ t
49 48 adantl ⊢ s ∪ t = ∅ ∧ x ∈ ∅ 1 𝑜 → s = ∅ ∧ ¬ t = ∅ → s = ∅ ∧ x ∈ ∅ 1 𝑜 ∨ ¬ t = ∅ ∧ x ∈ t
50 simpr ⊢ x ∈ s ∧ s = ∅ → s = ∅
51 id ⊢ s = ∅ → s = ∅
52 snsspr1 ⊢ ∅ ⊆ ∅ 1 𝑜
53 51 52 eqsstrdi ⊢ s = ∅ → s ⊆ ∅ 1 𝑜
54 53 sseld ⊢ s = ∅ → x ∈ s → x ∈ ∅ 1 𝑜
55 54 impcom ⊢ x ∈ s ∧ s = ∅ → x ∈ ∅ 1 𝑜
56 50 55 jca ⊢ x ∈ s ∧ s = ∅ → s = ∅ ∧ x ∈ ∅ 1 𝑜
57 56 orcd ⊢ x ∈ s ∧ s = ∅ → s = ∅ ∧ x ∈ ∅ 1 𝑜 ∨ ¬ t = ∅ ∧ x ∈ t
58 57 ex ⊢ x ∈ s → s = ∅ → s = ∅ ∧ x ∈ ∅ 1 𝑜 ∨ ¬ t = ∅ ∧ x ∈ t
59 olc ⊢ ¬ t = ∅ ∧ x ∈ t → s = ∅ ∧ x ∈ ∅ 1 𝑜 ∨ ¬ t = ∅ ∧ x ∈ t
60 59 expcom ⊢ x ∈ t → ¬ t = ∅ → s = ∅ ∧ x ∈ ∅ 1 𝑜 ∨ ¬ t = ∅ ∧ x ∈ t
61 58 60 jaoa ⊢ x ∈ s ∨ x ∈ t → s = ∅ ∧ ¬ t = ∅ → s = ∅ ∧ x ∈ ∅ 1 𝑜 ∨ ¬ t = ∅ ∧ x ∈ t
62 29 61 sylbi ⊢ x ∈ s ∪ t → s = ∅ ∧ ¬ t = ∅ → s = ∅ ∧ x ∈ ∅ 1 𝑜 ∨ ¬ t = ∅ ∧ x ∈ t
63 62 adantl ⊢ ¬ s ∪ t = ∅ ∧ x ∈ s ∪ t → s = ∅ ∧ ¬ t = ∅ → s = ∅ ∧ x ∈ ∅ 1 𝑜 ∨ ¬ t = ∅ ∧ x ∈ t
64 49 63 jaoi ⊢ s ∪ t = ∅ ∧ x ∈ ∅ 1 𝑜 ∨ ¬ s ∪ t = ∅ ∧ x ∈ s ∪ t → s = ∅ ∧ ¬ t = ∅ → s = ∅ ∧ x ∈ ∅ 1 𝑜 ∨ ¬ t = ∅ ∧ x ∈ t
65 olc ⊢ t = ∅ ∧ x ∈ ∅ 1 𝑜 → ¬ s = ∅ ∧ x ∈ s ∨ t = ∅ ∧ x ∈ ∅ 1 𝑜
66 65 expcom ⊢ x ∈ ∅ 1 𝑜 → t = ∅ → ¬ s = ∅ ∧ x ∈ s ∨ t = ∅ ∧ x ∈ ∅ 1 𝑜
67 66 adantl ⊢ s ∪ t = ∅ ∧ x ∈ ∅ 1 𝑜 → t = ∅ → ¬ s = ∅ ∧ x ∈ s ∨ t = ∅ ∧ x ∈ ∅ 1 𝑜
68 67 adantrd ⊢ s ∪ t = ∅ ∧ x ∈ ∅ 1 𝑜 → t = ∅ ∧ ¬ s = ∅ → ¬ s = ∅ ∧ x ∈ s ∨ t = ∅ ∧ x ∈ ∅ 1 𝑜
69 id ⊢ ¬ s = ∅ ∧ x ∈ s → ¬ s = ∅ ∧ x ∈ s
70 69 ex ⊢ ¬ s = ∅ → x ∈ s → ¬ s = ∅ ∧ x ∈ s
71 70 adantl ⊢ t = ∅ ∧ ¬ s = ∅ → x ∈ s → ¬ s = ∅ ∧ x ∈ s
72 id ⊢ t = ∅ → t = ∅
73 72 52 eqsstrdi ⊢ t = ∅ → t ⊆ ∅ 1 𝑜
74 73 sseld ⊢ t = ∅ → x ∈ t → x ∈ ∅ 1 𝑜
75 74 anc2li ⊢ t = ∅ → x ∈ t → t = ∅ ∧ x ∈ ∅ 1 𝑜
76 75 adantr ⊢ t = ∅ ∧ ¬ s = ∅ → x ∈ t → t = ∅ ∧ x ∈ ∅ 1 𝑜
77 71 76 orim12d ⊢ t = ∅ ∧ ¬ s = ∅ → x ∈ s ∨ x ∈ t → ¬ s = ∅ ∧ x ∈ s ∨ t = ∅ ∧ x ∈ ∅ 1 𝑜
78 77 com12 ⊢ x ∈ s ∨ x ∈ t → t = ∅ ∧ ¬ s = ∅ → ¬ s = ∅ ∧ x ∈ s ∨ t = ∅ ∧ x ∈ ∅ 1 𝑜
79 29 78 sylbi ⊢ x ∈ s ∪ t → t = ∅ ∧ ¬ s = ∅ → ¬ s = ∅ ∧ x ∈ s ∨ t = ∅ ∧ x ∈ ∅ 1 𝑜
80 79 adantl ⊢ ¬ s ∪ t = ∅ ∧ x ∈ s ∪ t → t = ∅ ∧ ¬ s = ∅ → ¬ s = ∅ ∧ x ∈ s ∨ t = ∅ ∧ x ∈ ∅ 1 𝑜
81 68 80 jaoi ⊢ s ∪ t = ∅ ∧ x ∈ ∅ 1 𝑜 ∨ ¬ s ∪ t = ∅ ∧ x ∈ s ∪ t → t = ∅ ∧ ¬ s = ∅ → ¬ s = ∅ ∧ x ∈ s ∨ t = ∅ ∧ x ∈ ∅ 1 𝑜
82 64 81 orim12d ⊢ s ∪ t = ∅ ∧ x ∈ ∅ 1 𝑜 ∨ ¬ s ∪ t = ∅ ∧ x ∈ s ∪ t → s = ∅ ∧ ¬ t = ∅ ∨ t = ∅ ∧ ¬ s = ∅ → s = ∅ ∧ x ∈ ∅ 1 𝑜 ∨ ¬ t = ∅ ∧ x ∈ t ∨ ¬ s = ∅ ∧ x ∈ s ∨ t = ∅ ∧ x ∈ ∅ 1 𝑜
83 82 com12 ⊢ s = ∅ ∧ ¬ t = ∅ ∨ t = ∅ ∧ ¬ s = ∅ → s ∪ t = ∅ ∧ x ∈ ∅ 1 𝑜 ∨ ¬ s ∪ t = ∅ ∧ x ∈ s ∪ t → s = ∅ ∧ x ∈ ∅ 1 𝑜 ∨ ¬ t = ∅ ∧ x ∈ t ∨ ¬ s = ∅ ∧ x ∈ s ∨ t = ∅ ∧ x ∈ ∅ 1 𝑜
84 or42 ⊢ s = ∅ ∧ x ∈ ∅ 1 𝑜 ∨ ¬ t = ∅ ∧ x ∈ t ∨ ¬ s = ∅ ∧ x ∈ s ∨ t = ∅ ∧ x ∈ ∅ 1 𝑜 ↔ s = ∅ ∧ x ∈ ∅ 1 𝑜 ∨ ¬ s = ∅ ∧ x ∈ s ∨ t = ∅ ∧ x ∈ ∅ 1 𝑜 ∨ ¬ t = ∅ ∧ x ∈ t
85 83 84 imbitrdi ⊢ s = ∅ ∧ ¬ t = ∅ ∨ t = ∅ ∧ ¬ s = ∅ → s ∪ t = ∅ ∧ x ∈ ∅ 1 𝑜 ∨ ¬ s ∪ t = ∅ ∧ x ∈ s ∪ t → s = ∅ ∧ x ∈ ∅ 1 𝑜 ∨ ¬ s = ∅ ∧ x ∈ s ∨ t = ∅ ∧ x ∈ ∅ 1 𝑜 ∨ ¬ t = ∅ ∧ x ∈ t
86 85 a1i ⊢ s ∈ 𝒫 3 𝑜 ∧ t ∈ 𝒫 3 𝑜 → s = ∅ ∧ ¬ t = ∅ ∨ t = ∅ ∧ ¬ s = ∅ → s ∪ t = ∅ ∧ x ∈ ∅ 1 𝑜 ∨ ¬ s ∪ t = ∅ ∧ x ∈ s ∪ t → s = ∅ ∧ x ∈ ∅ 1 𝑜 ∨ ¬ s = ∅ ∧ x ∈ s ∨ t = ∅ ∧ x ∈ ∅ 1 𝑜 ∨ ¬ t = ∅ ∧ x ∈ t
87 4exmid ⊢ s = ∅ ∧ t = ∅ ∨ ¬ s = ∅ ∧ ¬ t = ∅ ∨ s = ∅ ∧ ¬ t = ∅ ∨ t = ∅ ∧ ¬ s = ∅
88 87 a1i ⊢ s ∈ 𝒫 3 𝑜 ∧ t ∈ 𝒫 3 𝑜 → s = ∅ ∧ t = ∅ ∨ ¬ s = ∅ ∧ ¬ t = ∅ ∨ s = ∅ ∧ ¬ t = ∅ ∨ t = ∅ ∧ ¬ s = ∅
89 45 86 88 mpjaod ⊢ s ∈ 𝒫 3 𝑜 ∧ t ∈ 𝒫 3 𝑜 → s ∪ t = ∅ ∧ x ∈ ∅ 1 𝑜 ∨ ¬ s ∪ t = ∅ ∧ x ∈ s ∪ t → s = ∅ ∧ x ∈ ∅ 1 𝑜 ∨ ¬ s = ∅ ∧ x ∈ s ∨ t = ∅ ∧ x ∈ ∅ 1 𝑜 ∨ ¬ t = ∅ ∧ x ∈ t
90 2 89 biimtrid ⊢ s ∈ 𝒫 3 𝑜 ∧ t ∈ 𝒫 3 𝑜 → x ∈ if s ∪ t = ∅ ∅ 1 𝑜 s ∪ t → s = ∅ ∧ x ∈ ∅ 1 𝑜 ∨ ¬ s = ∅ ∧ x ∈ s ∨ t = ∅ ∧ x ∈ ∅ 1 𝑜 ∨ ¬ t = ∅ ∧ x ∈ t
91 elun ⊢ x ∈ if s = ∅ ∅ 1 𝑜 s ∪ if t = ∅ ∅ 1 𝑜 t ↔ x ∈ if s = ∅ ∅ 1 𝑜 s ∨ x ∈ if t = ∅ ∅ 1 𝑜 t
92 elif ⊢ x ∈ if s = ∅ ∅ 1 𝑜 s ↔ s = ∅ ∧ x ∈ ∅ 1 𝑜 ∨ ¬ s = ∅ ∧ x ∈ s
93 elif ⊢ x ∈ if t = ∅ ∅ 1 𝑜 t ↔ t = ∅ ∧ x ∈ ∅ 1 𝑜 ∨ ¬ t = ∅ ∧ x ∈ t
94 92 93 orbi12i ⊢ x ∈ if s = ∅ ∅ 1 𝑜 s ∨ x ∈ if t = ∅ ∅ 1 𝑜 t ↔ s = ∅ ∧ x ∈ ∅ 1 𝑜 ∨ ¬ s = ∅ ∧ x ∈ s ∨ t = ∅ ∧ x ∈ ∅ 1 𝑜 ∨ ¬ t = ∅ ∧ x ∈ t
95 91 94 sylbbr ⊢ s = ∅ ∧ x ∈ ∅ 1 𝑜 ∨ ¬ s = ∅ ∧ x ∈ s ∨ t = ∅ ∧ x ∈ ∅ 1 𝑜 ∨ ¬ t = ∅ ∧ x ∈ t → x ∈ if s = ∅ ∅ 1 𝑜 s ∪ if t = ∅ ∅ 1 𝑜 t
96 90 95 syl6 ⊢ s ∈ 𝒫 3 𝑜 ∧ t ∈ 𝒫 3 𝑜 → x ∈ if s ∪ t = ∅ ∅ 1 𝑜 s ∪ t → x ∈ if s = ∅ ∅ 1 𝑜 s ∪ if t = ∅ ∅ 1 𝑜 t
97 96 ssrdv ⊢ s ∈ 𝒫 3 𝑜 ∧ t ∈ 𝒫 3 𝑜 → if s ∪ t = ∅ ∅ 1 𝑜 s ∪ t ⊆ if s = ∅ ∅ 1 𝑜 s ∪ if t = ∅ ∅ 1 𝑜 t
98 pwuncl ⊢ s ∈ 𝒫 3 𝑜 ∧ t ∈ 𝒫 3 𝑜 → s ∪ t ∈ 𝒫 3 𝑜
99 eqeq1 ⊢ r = s ∪ t → r = ∅ ↔ s ∪ t = ∅
100 id ⊢ r = s ∪ t → r = s ∪ t
101 99 100 ifbieq2d ⊢ r = s ∪ t → if r = ∅ ∅ 1 𝑜 r = if s ∪ t = ∅ ∅ 1 𝑜 s ∪ t
102 prex ⊢ ∅ 1 𝑜 ∈ V
103 vex ⊢ s ∈ V
104 vex ⊢ t ∈ V
105 103 104 unex ⊢ s ∪ t ∈ V
106 102 105 ifex ⊢ if s ∪ t = ∅ ∅ 1 𝑜 s ∪ t ∈ V
107 101 1 106 fvmpt ⊢ s ∪ t ∈ 𝒫 3 𝑜 → K ⁡ s ∪ t = if s ∪ t = ∅ ∅ 1 𝑜 s ∪ t
108 98 107 syl ⊢ s ∈ 𝒫 3 𝑜 ∧ t ∈ 𝒫 3 𝑜 → K ⁡ s ∪ t = if s ∪ t = ∅ ∅ 1 𝑜 s ∪ t
109 eqeq1 ⊢ r = s → r = ∅ ↔ s = ∅
110 id ⊢ r = s → r = s
111 109 110 ifbieq2d ⊢ r = s → if r = ∅ ∅ 1 𝑜 r = if s = ∅ ∅ 1 𝑜 s
112 102 103 ifex ⊢ if s = ∅ ∅ 1 𝑜 s ∈ V
113 111 1 112 fvmpt ⊢ s ∈ 𝒫 3 𝑜 → K ⁡ s = if s = ∅ ∅ 1 𝑜 s
114 113 adantr ⊢ s ∈ 𝒫 3 𝑜 ∧ t ∈ 𝒫 3 𝑜 → K ⁡ s = if s = ∅ ∅ 1 𝑜 s
115 eqeq1 ⊢ r = t → r = ∅ ↔ t = ∅
116 id ⊢ r = t → r = t
117 115 116 ifbieq2d ⊢ r = t → if r = ∅ ∅ 1 𝑜 r = if t = ∅ ∅ 1 𝑜 t
118 102 104 ifex ⊢ if t = ∅ ∅ 1 𝑜 t ∈ V
119 117 1 118 fvmpt ⊢ t ∈ 𝒫 3 𝑜 → K ⁡ t = if t = ∅ ∅ 1 𝑜 t
120 119 adantl ⊢ s ∈ 𝒫 3 𝑜 ∧ t ∈ 𝒫 3 𝑜 → K ⁡ t = if t = ∅ ∅ 1 𝑜 t
121 114 120 uneq12d ⊢ s ∈ 𝒫 3 𝑜 ∧ t ∈ 𝒫 3 𝑜 → K ⁡ s ∪ K ⁡ t = if s = ∅ ∅ 1 𝑜 s ∪ if t = ∅ ∅ 1 𝑜 t
122 97 108 121 3sstr4d ⊢ s ∈ 𝒫 3 𝑜 ∧ t ∈ 𝒫 3 𝑜 → K ⁡ s ∪ t ⊆ K ⁡ s ∪ K ⁡ t
123 122 rgen2 ⊢ ∀ s ∈ 𝒫 3 𝑜 ∀ t ∈ 𝒫 3 𝑜 K ⁡ s ∪ t ⊆ K ⁡ s ∪ K ⁡ t