| Step | Hyp | Ref | Expression | 
						
							| 1 |  | ntrcls.o | ⊢ 𝑂  =  ( 𝑖  ∈  V  ↦  ( 𝑘  ∈  ( 𝒫  𝑖  ↑m  𝒫  𝑖 )  ↦  ( 𝑗  ∈  𝒫  𝑖  ↦  ( 𝑖  ∖  ( 𝑘 ‘ ( 𝑖  ∖  𝑗 ) ) ) ) ) ) | 
						
							| 2 |  | ntrcls.d | ⊢ 𝐷  =  ( 𝑂 ‘ 𝐵 ) | 
						
							| 3 |  | ntrcls.r | ⊢ ( 𝜑  →  𝐼 𝐷 𝐾 ) | 
						
							| 4 |  | fveq2 | ⊢ ( 𝑠  =  𝑎  →  ( 𝐼 ‘ 𝑠 )  =  ( 𝐼 ‘ 𝑎 ) ) | 
						
							| 5 | 4 | ineq1d | ⊢ ( 𝑠  =  𝑎  →  ( ( 𝐼 ‘ 𝑠 )  ∩  ( 𝐼 ‘ 𝑡 ) )  =  ( ( 𝐼 ‘ 𝑎 )  ∩  ( 𝐼 ‘ 𝑡 ) ) ) | 
						
							| 6 |  | ineq1 | ⊢ ( 𝑠  =  𝑎  →  ( 𝑠  ∩  𝑡 )  =  ( 𝑎  ∩  𝑡 ) ) | 
						
							| 7 | 6 | fveq2d | ⊢ ( 𝑠  =  𝑎  →  ( 𝐼 ‘ ( 𝑠  ∩  𝑡 ) )  =  ( 𝐼 ‘ ( 𝑎  ∩  𝑡 ) ) ) | 
						
							| 8 | 5 7 | sseq12d | ⊢ ( 𝑠  =  𝑎  →  ( ( ( 𝐼 ‘ 𝑠 )  ∩  ( 𝐼 ‘ 𝑡 ) )  ⊆  ( 𝐼 ‘ ( 𝑠  ∩  𝑡 ) )  ↔  ( ( 𝐼 ‘ 𝑎 )  ∩  ( 𝐼 ‘ 𝑡 ) )  ⊆  ( 𝐼 ‘ ( 𝑎  ∩  𝑡 ) ) ) ) | 
						
							| 9 |  | fveq2 | ⊢ ( 𝑡  =  𝑏  →  ( 𝐼 ‘ 𝑡 )  =  ( 𝐼 ‘ 𝑏 ) ) | 
						
							| 10 | 9 | ineq2d | ⊢ ( 𝑡  =  𝑏  →  ( ( 𝐼 ‘ 𝑎 )  ∩  ( 𝐼 ‘ 𝑡 ) )  =  ( ( 𝐼 ‘ 𝑎 )  ∩  ( 𝐼 ‘ 𝑏 ) ) ) | 
						
							| 11 |  | ineq2 | ⊢ ( 𝑡  =  𝑏  →  ( 𝑎  ∩  𝑡 )  =  ( 𝑎  ∩  𝑏 ) ) | 
						
							| 12 | 11 | fveq2d | ⊢ ( 𝑡  =  𝑏  →  ( 𝐼 ‘ ( 𝑎  ∩  𝑡 ) )  =  ( 𝐼 ‘ ( 𝑎  ∩  𝑏 ) ) ) | 
						
							| 13 | 10 12 | sseq12d | ⊢ ( 𝑡  =  𝑏  →  ( ( ( 𝐼 ‘ 𝑎 )  ∩  ( 𝐼 ‘ 𝑡 ) )  ⊆  ( 𝐼 ‘ ( 𝑎  ∩  𝑡 ) )  ↔  ( ( 𝐼 ‘ 𝑎 )  ∩  ( 𝐼 ‘ 𝑏 ) )  ⊆  ( 𝐼 ‘ ( 𝑎  ∩  𝑏 ) ) ) ) | 
						
							| 14 | 8 13 | cbvral2vw | ⊢ ( ∀ 𝑠  ∈  𝒫  𝐵 ∀ 𝑡  ∈  𝒫  𝐵 ( ( 𝐼 ‘ 𝑠 )  ∩  ( 𝐼 ‘ 𝑡 ) )  ⊆  ( 𝐼 ‘ ( 𝑠  ∩  𝑡 ) )  ↔  ∀ 𝑎  ∈  𝒫  𝐵 ∀ 𝑏  ∈  𝒫  𝐵 ( ( 𝐼 ‘ 𝑎 )  ∩  ( 𝐼 ‘ 𝑏 ) )  ⊆  ( 𝐼 ‘ ( 𝑎  ∩  𝑏 ) ) ) | 
						
							| 15 | 2 3 | ntrclsbex | ⊢ ( 𝜑  →  𝐵  ∈  V ) | 
						
							| 16 |  | difssd | ⊢ ( 𝜑  →  ( 𝐵  ∖  𝑠 )  ⊆  𝐵 ) | 
						
							| 17 | 15 16 | sselpwd | ⊢ ( 𝜑  →  ( 𝐵  ∖  𝑠 )  ∈  𝒫  𝐵 ) | 
						
							| 18 | 17 | adantr | ⊢ ( ( 𝜑  ∧  𝑠  ∈  𝒫  𝐵 )  →  ( 𝐵  ∖  𝑠 )  ∈  𝒫  𝐵 ) | 
						
							| 19 |  | elpwi | ⊢ ( 𝑎  ∈  𝒫  𝐵  →  𝑎  ⊆  𝐵 ) | 
						
							| 20 |  | simpl | ⊢ ( ( 𝐵  ∈  V  ∧  𝑎  ⊆  𝐵 )  →  𝐵  ∈  V ) | 
						
							| 21 |  | difssd | ⊢ ( ( 𝐵  ∈  V  ∧  𝑎  ⊆  𝐵 )  →  ( 𝐵  ∖  𝑎 )  ⊆  𝐵 ) | 
						
							| 22 | 20 21 | sselpwd | ⊢ ( ( 𝐵  ∈  V  ∧  𝑎  ⊆  𝐵 )  →  ( 𝐵  ∖  𝑎 )  ∈  𝒫  𝐵 ) | 
						
							| 23 |  | simpr | ⊢ ( ( ( 𝐵  ∈  V  ∧  𝑎  ⊆  𝐵 )  ∧  𝑠  =  ( 𝐵  ∖  𝑎 ) )  →  𝑠  =  ( 𝐵  ∖  𝑎 ) ) | 
						
							| 24 | 23 | difeq2d | ⊢ ( ( ( 𝐵  ∈  V  ∧  𝑎  ⊆  𝐵 )  ∧  𝑠  =  ( 𝐵  ∖  𝑎 ) )  →  ( 𝐵  ∖  𝑠 )  =  ( 𝐵  ∖  ( 𝐵  ∖  𝑎 ) ) ) | 
						
							| 25 | 24 | eqeq2d | ⊢ ( ( ( 𝐵  ∈  V  ∧  𝑎  ⊆  𝐵 )  ∧  𝑠  =  ( 𝐵  ∖  𝑎 ) )  →  ( 𝑎  =  ( 𝐵  ∖  𝑠 )  ↔  𝑎  =  ( 𝐵  ∖  ( 𝐵  ∖  𝑎 ) ) ) ) | 
						
							| 26 |  | eqcom | ⊢ ( 𝑎  =  ( 𝐵  ∖  ( 𝐵  ∖  𝑎 ) )  ↔  ( 𝐵  ∖  ( 𝐵  ∖  𝑎 ) )  =  𝑎 ) | 
						
							| 27 | 25 26 | bitrdi | ⊢ ( ( ( 𝐵  ∈  V  ∧  𝑎  ⊆  𝐵 )  ∧  𝑠  =  ( 𝐵  ∖  𝑎 ) )  →  ( 𝑎  =  ( 𝐵  ∖  𝑠 )  ↔  ( 𝐵  ∖  ( 𝐵  ∖  𝑎 ) )  =  𝑎 ) ) | 
						
							| 28 |  | dfss4 | ⊢ ( 𝑎  ⊆  𝐵  ↔  ( 𝐵  ∖  ( 𝐵  ∖  𝑎 ) )  =  𝑎 ) | 
						
							| 29 | 28 | biimpi | ⊢ ( 𝑎  ⊆  𝐵  →  ( 𝐵  ∖  ( 𝐵  ∖  𝑎 ) )  =  𝑎 ) | 
						
							| 30 | 29 | adantl | ⊢ ( ( 𝐵  ∈  V  ∧  𝑎  ⊆  𝐵 )  →  ( 𝐵  ∖  ( 𝐵  ∖  𝑎 ) )  =  𝑎 ) | 
						
							| 31 | 22 27 30 | rspcedvd | ⊢ ( ( 𝐵  ∈  V  ∧  𝑎  ⊆  𝐵 )  →  ∃ 𝑠  ∈  𝒫  𝐵 𝑎  =  ( 𝐵  ∖  𝑠 ) ) | 
						
							| 32 | 15 19 31 | syl2an | ⊢ ( ( 𝜑  ∧  𝑎  ∈  𝒫  𝐵 )  →  ∃ 𝑠  ∈  𝒫  𝐵 𝑎  =  ( 𝐵  ∖  𝑠 ) ) | 
						
							| 33 |  | simpl1 | ⊢ ( ( ( 𝜑  ∧  𝑠  ∈  𝒫  𝐵  ∧  𝑎  =  ( 𝐵  ∖  𝑠 ) )  ∧  𝑡  ∈  𝒫  𝐵 )  →  𝜑 ) | 
						
							| 34 |  | difssd | ⊢ ( 𝜑  →  ( 𝐵  ∖  𝑡 )  ⊆  𝐵 ) | 
						
							| 35 | 15 34 | sselpwd | ⊢ ( 𝜑  →  ( 𝐵  ∖  𝑡 )  ∈  𝒫  𝐵 ) | 
						
							| 36 | 33 35 | syl | ⊢ ( ( ( 𝜑  ∧  𝑠  ∈  𝒫  𝐵  ∧  𝑎  =  ( 𝐵  ∖  𝑠 ) )  ∧  𝑡  ∈  𝒫  𝐵 )  →  ( 𝐵  ∖  𝑡 )  ∈  𝒫  𝐵 ) | 
						
							| 37 |  | elpwi | ⊢ ( 𝑏  ∈  𝒫  𝐵  →  𝑏  ⊆  𝐵 ) | 
						
							| 38 |  | simpl | ⊢ ( ( 𝐵  ∈  V  ∧  𝑏  ⊆  𝐵 )  →  𝐵  ∈  V ) | 
						
							| 39 |  | difssd | ⊢ ( ( 𝐵  ∈  V  ∧  𝑏  ⊆  𝐵 )  →  ( 𝐵  ∖  𝑏 )  ⊆  𝐵 ) | 
						
							| 40 | 38 39 | sselpwd | ⊢ ( ( 𝐵  ∈  V  ∧  𝑏  ⊆  𝐵 )  →  ( 𝐵  ∖  𝑏 )  ∈  𝒫  𝐵 ) | 
						
							| 41 |  | simpr | ⊢ ( ( ( 𝐵  ∈  V  ∧  𝑏  ⊆  𝐵 )  ∧  𝑡  =  ( 𝐵  ∖  𝑏 ) )  →  𝑡  =  ( 𝐵  ∖  𝑏 ) ) | 
						
							| 42 | 41 | difeq2d | ⊢ ( ( ( 𝐵  ∈  V  ∧  𝑏  ⊆  𝐵 )  ∧  𝑡  =  ( 𝐵  ∖  𝑏 ) )  →  ( 𝐵  ∖  𝑡 )  =  ( 𝐵  ∖  ( 𝐵  ∖  𝑏 ) ) ) | 
						
							| 43 | 42 | eqeq2d | ⊢ ( ( ( 𝐵  ∈  V  ∧  𝑏  ⊆  𝐵 )  ∧  𝑡  =  ( 𝐵  ∖  𝑏 ) )  →  ( 𝑏  =  ( 𝐵  ∖  𝑡 )  ↔  𝑏  =  ( 𝐵  ∖  ( 𝐵  ∖  𝑏 ) ) ) ) | 
						
							| 44 |  | eqcom | ⊢ ( 𝑏  =  ( 𝐵  ∖  ( 𝐵  ∖  𝑏 ) )  ↔  ( 𝐵  ∖  ( 𝐵  ∖  𝑏 ) )  =  𝑏 ) | 
						
							| 45 | 43 44 | bitrdi | ⊢ ( ( ( 𝐵  ∈  V  ∧  𝑏  ⊆  𝐵 )  ∧  𝑡  =  ( 𝐵  ∖  𝑏 ) )  →  ( 𝑏  =  ( 𝐵  ∖  𝑡 )  ↔  ( 𝐵  ∖  ( 𝐵  ∖  𝑏 ) )  =  𝑏 ) ) | 
						
							| 46 |  | dfss4 | ⊢ ( 𝑏  ⊆  𝐵  ↔  ( 𝐵  ∖  ( 𝐵  ∖  𝑏 ) )  =  𝑏 ) | 
						
							| 47 | 46 | biimpi | ⊢ ( 𝑏  ⊆  𝐵  →  ( 𝐵  ∖  ( 𝐵  ∖  𝑏 ) )  =  𝑏 ) | 
						
							| 48 | 47 | adantl | ⊢ ( ( 𝐵  ∈  V  ∧  𝑏  ⊆  𝐵 )  →  ( 𝐵  ∖  ( 𝐵  ∖  𝑏 ) )  =  𝑏 ) | 
						
							| 49 | 40 45 48 | rspcedvd | ⊢ ( ( 𝐵  ∈  V  ∧  𝑏  ⊆  𝐵 )  →  ∃ 𝑡  ∈  𝒫  𝐵 𝑏  =  ( 𝐵  ∖  𝑡 ) ) | 
						
							| 50 | 15 37 49 | syl2an | ⊢ ( ( 𝜑  ∧  𝑏  ∈  𝒫  𝐵 )  →  ∃ 𝑡  ∈  𝒫  𝐵 𝑏  =  ( 𝐵  ∖  𝑡 ) ) | 
						
							| 51 | 50 | 3ad2antl1 | ⊢ ( ( ( 𝜑  ∧  𝑠  ∈  𝒫  𝐵  ∧  𝑎  =  ( 𝐵  ∖  𝑠 ) )  ∧  𝑏  ∈  𝒫  𝐵 )  →  ∃ 𝑡  ∈  𝒫  𝐵 𝑏  =  ( 𝐵  ∖  𝑡 ) ) | 
						
							| 52 |  | simp13 | ⊢ ( ( ( 𝜑  ∧  𝑠  ∈  𝒫  𝐵  ∧  𝑎  =  ( 𝐵  ∖  𝑠 ) )  ∧  𝑡  ∈  𝒫  𝐵  ∧  𝑏  =  ( 𝐵  ∖  𝑡 ) )  →  𝑎  =  ( 𝐵  ∖  𝑠 ) ) | 
						
							| 53 |  | fveq2 | ⊢ ( 𝑎  =  ( 𝐵  ∖  𝑠 )  →  ( 𝐼 ‘ 𝑎 )  =  ( 𝐼 ‘ ( 𝐵  ∖  𝑠 ) ) ) | 
						
							| 54 | 53 | ineq1d | ⊢ ( 𝑎  =  ( 𝐵  ∖  𝑠 )  →  ( ( 𝐼 ‘ 𝑎 )  ∩  ( 𝐼 ‘ 𝑏 ) )  =  ( ( 𝐼 ‘ ( 𝐵  ∖  𝑠 ) )  ∩  ( 𝐼 ‘ 𝑏 ) ) ) | 
						
							| 55 |  | ineq1 | ⊢ ( 𝑎  =  ( 𝐵  ∖  𝑠 )  →  ( 𝑎  ∩  𝑏 )  =  ( ( 𝐵  ∖  𝑠 )  ∩  𝑏 ) ) | 
						
							| 56 | 55 | fveq2d | ⊢ ( 𝑎  =  ( 𝐵  ∖  𝑠 )  →  ( 𝐼 ‘ ( 𝑎  ∩  𝑏 ) )  =  ( 𝐼 ‘ ( ( 𝐵  ∖  𝑠 )  ∩  𝑏 ) ) ) | 
						
							| 57 | 54 56 | sseq12d | ⊢ ( 𝑎  =  ( 𝐵  ∖  𝑠 )  →  ( ( ( 𝐼 ‘ 𝑎 )  ∩  ( 𝐼 ‘ 𝑏 ) )  ⊆  ( 𝐼 ‘ ( 𝑎  ∩  𝑏 ) )  ↔  ( ( 𝐼 ‘ ( 𝐵  ∖  𝑠 ) )  ∩  ( 𝐼 ‘ 𝑏 ) )  ⊆  ( 𝐼 ‘ ( ( 𝐵  ∖  𝑠 )  ∩  𝑏 ) ) ) ) | 
						
							| 58 | 52 57 | syl | ⊢ ( ( ( 𝜑  ∧  𝑠  ∈  𝒫  𝐵  ∧  𝑎  =  ( 𝐵  ∖  𝑠 ) )  ∧  𝑡  ∈  𝒫  𝐵  ∧  𝑏  =  ( 𝐵  ∖  𝑡 ) )  →  ( ( ( 𝐼 ‘ 𝑎 )  ∩  ( 𝐼 ‘ 𝑏 ) )  ⊆  ( 𝐼 ‘ ( 𝑎  ∩  𝑏 ) )  ↔  ( ( 𝐼 ‘ ( 𝐵  ∖  𝑠 ) )  ∩  ( 𝐼 ‘ 𝑏 ) )  ⊆  ( 𝐼 ‘ ( ( 𝐵  ∖  𝑠 )  ∩  𝑏 ) ) ) ) | 
						
							| 59 |  | fveq2 | ⊢ ( 𝑏  =  ( 𝐵  ∖  𝑡 )  →  ( 𝐼 ‘ 𝑏 )  =  ( 𝐼 ‘ ( 𝐵  ∖  𝑡 ) ) ) | 
						
							| 60 | 59 | ineq2d | ⊢ ( 𝑏  =  ( 𝐵  ∖  𝑡 )  →  ( ( 𝐼 ‘ ( 𝐵  ∖  𝑠 ) )  ∩  ( 𝐼 ‘ 𝑏 ) )  =  ( ( 𝐼 ‘ ( 𝐵  ∖  𝑠 ) )  ∩  ( 𝐼 ‘ ( 𝐵  ∖  𝑡 ) ) ) ) | 
						
							| 61 |  | ineq2 | ⊢ ( 𝑏  =  ( 𝐵  ∖  𝑡 )  →  ( ( 𝐵  ∖  𝑠 )  ∩  𝑏 )  =  ( ( 𝐵  ∖  𝑠 )  ∩  ( 𝐵  ∖  𝑡 ) ) ) | 
						
							| 62 |  | difundi | ⊢ ( 𝐵  ∖  ( 𝑠  ∪  𝑡 ) )  =  ( ( 𝐵  ∖  𝑠 )  ∩  ( 𝐵  ∖  𝑡 ) ) | 
						
							| 63 | 61 62 | eqtr4di | ⊢ ( 𝑏  =  ( 𝐵  ∖  𝑡 )  →  ( ( 𝐵  ∖  𝑠 )  ∩  𝑏 )  =  ( 𝐵  ∖  ( 𝑠  ∪  𝑡 ) ) ) | 
						
							| 64 | 63 | fveq2d | ⊢ ( 𝑏  =  ( 𝐵  ∖  𝑡 )  →  ( 𝐼 ‘ ( ( 𝐵  ∖  𝑠 )  ∩  𝑏 ) )  =  ( 𝐼 ‘ ( 𝐵  ∖  ( 𝑠  ∪  𝑡 ) ) ) ) | 
						
							| 65 | 60 64 | sseq12d | ⊢ ( 𝑏  =  ( 𝐵  ∖  𝑡 )  →  ( ( ( 𝐼 ‘ ( 𝐵  ∖  𝑠 ) )  ∩  ( 𝐼 ‘ 𝑏 ) )  ⊆  ( 𝐼 ‘ ( ( 𝐵  ∖  𝑠 )  ∩  𝑏 ) )  ↔  ( ( 𝐼 ‘ ( 𝐵  ∖  𝑠 ) )  ∩  ( 𝐼 ‘ ( 𝐵  ∖  𝑡 ) ) )  ⊆  ( 𝐼 ‘ ( 𝐵  ∖  ( 𝑠  ∪  𝑡 ) ) ) ) ) | 
						
							| 66 | 65 | 3ad2ant3 | ⊢ ( ( ( 𝜑  ∧  𝑠  ∈  𝒫  𝐵  ∧  𝑎  =  ( 𝐵  ∖  𝑠 ) )  ∧  𝑡  ∈  𝒫  𝐵  ∧  𝑏  =  ( 𝐵  ∖  𝑡 ) )  →  ( ( ( 𝐼 ‘ ( 𝐵  ∖  𝑠 ) )  ∩  ( 𝐼 ‘ 𝑏 ) )  ⊆  ( 𝐼 ‘ ( ( 𝐵  ∖  𝑠 )  ∩  𝑏 ) )  ↔  ( ( 𝐼 ‘ ( 𝐵  ∖  𝑠 ) )  ∩  ( 𝐼 ‘ ( 𝐵  ∖  𝑡 ) ) )  ⊆  ( 𝐼 ‘ ( 𝐵  ∖  ( 𝑠  ∪  𝑡 ) ) ) ) ) | 
						
							| 67 |  | simp11 | ⊢ ( ( ( 𝜑  ∧  𝑠  ∈  𝒫  𝐵  ∧  𝑎  =  ( 𝐵  ∖  𝑠 ) )  ∧  𝑡  ∈  𝒫  𝐵  ∧  𝑏  =  ( 𝐵  ∖  𝑡 ) )  →  𝜑 ) | 
						
							| 68 | 1 2 3 | ntrclsiex | ⊢ ( 𝜑  →  𝐼  ∈  ( 𝒫  𝐵  ↑m  𝒫  𝐵 ) ) | 
						
							| 69 | 68 15 | jca | ⊢ ( 𝜑  →  ( 𝐼  ∈  ( 𝒫  𝐵  ↑m  𝒫  𝐵 )  ∧  𝐵  ∈  V ) ) | 
						
							| 70 |  | elmapi | ⊢ ( 𝐼  ∈  ( 𝒫  𝐵  ↑m  𝒫  𝐵 )  →  𝐼 : 𝒫  𝐵 ⟶ 𝒫  𝐵 ) | 
						
							| 71 | 70 | adantr | ⊢ ( ( 𝐼  ∈  ( 𝒫  𝐵  ↑m  𝒫  𝐵 )  ∧  𝐵  ∈  V )  →  𝐼 : 𝒫  𝐵 ⟶ 𝒫  𝐵 ) | 
						
							| 72 |  | simpr | ⊢ ( ( 𝐼  ∈  ( 𝒫  𝐵  ↑m  𝒫  𝐵 )  ∧  𝐵  ∈  V )  →  𝐵  ∈  V ) | 
						
							| 73 |  | difssd | ⊢ ( ( 𝐼  ∈  ( 𝒫  𝐵  ↑m  𝒫  𝐵 )  ∧  𝐵  ∈  V )  →  ( 𝐵  ∖  𝑠 )  ⊆  𝐵 ) | 
						
							| 74 | 72 73 | sselpwd | ⊢ ( ( 𝐼  ∈  ( 𝒫  𝐵  ↑m  𝒫  𝐵 )  ∧  𝐵  ∈  V )  →  ( 𝐵  ∖  𝑠 )  ∈  𝒫  𝐵 ) | 
						
							| 75 | 71 74 | ffvelcdmd | ⊢ ( ( 𝐼  ∈  ( 𝒫  𝐵  ↑m  𝒫  𝐵 )  ∧  𝐵  ∈  V )  →  ( 𝐼 ‘ ( 𝐵  ∖  𝑠 ) )  ∈  𝒫  𝐵 ) | 
						
							| 76 | 75 | elpwid | ⊢ ( ( 𝐼  ∈  ( 𝒫  𝐵  ↑m  𝒫  𝐵 )  ∧  𝐵  ∈  V )  →  ( 𝐼 ‘ ( 𝐵  ∖  𝑠 ) )  ⊆  𝐵 ) | 
						
							| 77 |  | orc | ⊢ ( ( 𝐼 ‘ ( 𝐵  ∖  𝑠 ) )  ⊆  𝐵  →  ( ( 𝐼 ‘ ( 𝐵  ∖  𝑠 ) )  ⊆  𝐵  ∨  ( 𝐼 ‘ ( 𝐵  ∖  𝑡 ) )  ⊆  𝐵 ) ) | 
						
							| 78 |  | inss | ⊢ ( ( ( 𝐼 ‘ ( 𝐵  ∖  𝑠 ) )  ⊆  𝐵  ∨  ( 𝐼 ‘ ( 𝐵  ∖  𝑡 ) )  ⊆  𝐵 )  →  ( ( 𝐼 ‘ ( 𝐵  ∖  𝑠 ) )  ∩  ( 𝐼 ‘ ( 𝐵  ∖  𝑡 ) ) )  ⊆  𝐵 ) | 
						
							| 79 | 76 77 78 | 3syl | ⊢ ( ( 𝐼  ∈  ( 𝒫  𝐵  ↑m  𝒫  𝐵 )  ∧  𝐵  ∈  V )  →  ( ( 𝐼 ‘ ( 𝐵  ∖  𝑠 ) )  ∩  ( 𝐼 ‘ ( 𝐵  ∖  𝑡 ) ) )  ⊆  𝐵 ) | 
						
							| 80 |  | difssd | ⊢ ( ( 𝐼  ∈  ( 𝒫  𝐵  ↑m  𝒫  𝐵 )  ∧  𝐵  ∈  V )  →  ( 𝐵  ∖  ( 𝑠  ∪  𝑡 ) )  ⊆  𝐵 ) | 
						
							| 81 | 72 80 | sselpwd | ⊢ ( ( 𝐼  ∈  ( 𝒫  𝐵  ↑m  𝒫  𝐵 )  ∧  𝐵  ∈  V )  →  ( 𝐵  ∖  ( 𝑠  ∪  𝑡 ) )  ∈  𝒫  𝐵 ) | 
						
							| 82 | 71 81 | ffvelcdmd | ⊢ ( ( 𝐼  ∈  ( 𝒫  𝐵  ↑m  𝒫  𝐵 )  ∧  𝐵  ∈  V )  →  ( 𝐼 ‘ ( 𝐵  ∖  ( 𝑠  ∪  𝑡 ) ) )  ∈  𝒫  𝐵 ) | 
						
							| 83 | 82 | elpwid | ⊢ ( ( 𝐼  ∈  ( 𝒫  𝐵  ↑m  𝒫  𝐵 )  ∧  𝐵  ∈  V )  →  ( 𝐼 ‘ ( 𝐵  ∖  ( 𝑠  ∪  𝑡 ) ) )  ⊆  𝐵 ) | 
						
							| 84 | 79 83 | jca | ⊢ ( ( 𝐼  ∈  ( 𝒫  𝐵  ↑m  𝒫  𝐵 )  ∧  𝐵  ∈  V )  →  ( ( ( 𝐼 ‘ ( 𝐵  ∖  𝑠 ) )  ∩  ( 𝐼 ‘ ( 𝐵  ∖  𝑡 ) ) )  ⊆  𝐵  ∧  ( 𝐼 ‘ ( 𝐵  ∖  ( 𝑠  ∪  𝑡 ) ) )  ⊆  𝐵 ) ) | 
						
							| 85 |  | sscon34b | ⊢ ( ( ( ( 𝐼 ‘ ( 𝐵  ∖  𝑠 ) )  ∩  ( 𝐼 ‘ ( 𝐵  ∖  𝑡 ) ) )  ⊆  𝐵  ∧  ( 𝐼 ‘ ( 𝐵  ∖  ( 𝑠  ∪  𝑡 ) ) )  ⊆  𝐵 )  →  ( ( ( 𝐼 ‘ ( 𝐵  ∖  𝑠 ) )  ∩  ( 𝐼 ‘ ( 𝐵  ∖  𝑡 ) ) )  ⊆  ( 𝐼 ‘ ( 𝐵  ∖  ( 𝑠  ∪  𝑡 ) ) )  ↔  ( 𝐵  ∖  ( 𝐼 ‘ ( 𝐵  ∖  ( 𝑠  ∪  𝑡 ) ) ) )  ⊆  ( 𝐵  ∖  ( ( 𝐼 ‘ ( 𝐵  ∖  𝑠 ) )  ∩  ( 𝐼 ‘ ( 𝐵  ∖  𝑡 ) ) ) ) ) ) | 
						
							| 86 | 67 69 84 85 | 4syl | ⊢ ( ( ( 𝜑  ∧  𝑠  ∈  𝒫  𝐵  ∧  𝑎  =  ( 𝐵  ∖  𝑠 ) )  ∧  𝑡  ∈  𝒫  𝐵  ∧  𝑏  =  ( 𝐵  ∖  𝑡 ) )  →  ( ( ( 𝐼 ‘ ( 𝐵  ∖  𝑠 ) )  ∩  ( 𝐼 ‘ ( 𝐵  ∖  𝑡 ) ) )  ⊆  ( 𝐼 ‘ ( 𝐵  ∖  ( 𝑠  ∪  𝑡 ) ) )  ↔  ( 𝐵  ∖  ( 𝐼 ‘ ( 𝐵  ∖  ( 𝑠  ∪  𝑡 ) ) ) )  ⊆  ( 𝐵  ∖  ( ( 𝐼 ‘ ( 𝐵  ∖  𝑠 ) )  ∩  ( 𝐼 ‘ ( 𝐵  ∖  𝑡 ) ) ) ) ) ) | 
						
							| 87 |  | difindi | ⊢ ( 𝐵  ∖  ( ( 𝐼 ‘ ( 𝐵  ∖  𝑠 ) )  ∩  ( 𝐼 ‘ ( 𝐵  ∖  𝑡 ) ) ) )  =  ( ( 𝐵  ∖  ( 𝐼 ‘ ( 𝐵  ∖  𝑠 ) ) )  ∪  ( 𝐵  ∖  ( 𝐼 ‘ ( 𝐵  ∖  𝑡 ) ) ) ) | 
						
							| 88 | 87 | sseq2i | ⊢ ( ( 𝐵  ∖  ( 𝐼 ‘ ( 𝐵  ∖  ( 𝑠  ∪  𝑡 ) ) ) )  ⊆  ( 𝐵  ∖  ( ( 𝐼 ‘ ( 𝐵  ∖  𝑠 ) )  ∩  ( 𝐼 ‘ ( 𝐵  ∖  𝑡 ) ) ) )  ↔  ( 𝐵  ∖  ( 𝐼 ‘ ( 𝐵  ∖  ( 𝑠  ∪  𝑡 ) ) ) )  ⊆  ( ( 𝐵  ∖  ( 𝐼 ‘ ( 𝐵  ∖  𝑠 ) ) )  ∪  ( 𝐵  ∖  ( 𝐼 ‘ ( 𝐵  ∖  𝑡 ) ) ) ) ) | 
						
							| 89 | 88 | a1i | ⊢ ( ( ( 𝜑  ∧  𝑠  ∈  𝒫  𝐵  ∧  𝑎  =  ( 𝐵  ∖  𝑠 ) )  ∧  𝑡  ∈  𝒫  𝐵  ∧  𝑏  =  ( 𝐵  ∖  𝑡 ) )  →  ( ( 𝐵  ∖  ( 𝐼 ‘ ( 𝐵  ∖  ( 𝑠  ∪  𝑡 ) ) ) )  ⊆  ( 𝐵  ∖  ( ( 𝐼 ‘ ( 𝐵  ∖  𝑠 ) )  ∩  ( 𝐼 ‘ ( 𝐵  ∖  𝑡 ) ) ) )  ↔  ( 𝐵  ∖  ( 𝐼 ‘ ( 𝐵  ∖  ( 𝑠  ∪  𝑡 ) ) ) )  ⊆  ( ( 𝐵  ∖  ( 𝐼 ‘ ( 𝐵  ∖  𝑠 ) ) )  ∪  ( 𝐵  ∖  ( 𝐼 ‘ ( 𝐵  ∖  𝑡 ) ) ) ) ) ) | 
						
							| 90 | 67 15 | syl | ⊢ ( ( ( 𝜑  ∧  𝑠  ∈  𝒫  𝐵  ∧  𝑎  =  ( 𝐵  ∖  𝑠 ) )  ∧  𝑡  ∈  𝒫  𝐵  ∧  𝑏  =  ( 𝐵  ∖  𝑡 ) )  →  𝐵  ∈  V ) | 
						
							| 91 | 67 68 | syl | ⊢ ( ( ( 𝜑  ∧  𝑠  ∈  𝒫  𝐵  ∧  𝑎  =  ( 𝐵  ∖  𝑠 ) )  ∧  𝑡  ∈  𝒫  𝐵  ∧  𝑏  =  ( 𝐵  ∖  𝑡 ) )  →  𝐼  ∈  ( 𝒫  𝐵  ↑m  𝒫  𝐵 ) ) | 
						
							| 92 |  | simp12 | ⊢ ( ( ( 𝜑  ∧  𝑠  ∈  𝒫  𝐵  ∧  𝑎  =  ( 𝐵  ∖  𝑠 ) )  ∧  𝑡  ∈  𝒫  𝐵  ∧  𝑏  =  ( 𝐵  ∖  𝑡 ) )  →  𝑠  ∈  𝒫  𝐵 ) | 
						
							| 93 |  | rp-simp2 | ⊢ ( ( ( 𝜑  ∧  𝑠  ∈  𝒫  𝐵  ∧  𝑎  =  ( 𝐵  ∖  𝑠 ) )  ∧  𝑡  ∈  𝒫  𝐵  ∧  𝑏  =  ( 𝐵  ∖  𝑡 ) )  →  𝑡  ∈  𝒫  𝐵 ) | 
						
							| 94 |  | simpl2 | ⊢ ( ( ( 𝜑  ∧  𝐵  ∈  V  ∧  𝐼  ∈  ( 𝒫  𝐵  ↑m  𝒫  𝐵 ) )  ∧  ( 𝑠  ∈  𝒫  𝐵  ∧  𝑡  ∈  𝒫  𝐵 ) )  →  𝐵  ∈  V ) | 
						
							| 95 |  | simpl3 | ⊢ ( ( ( 𝜑  ∧  𝐵  ∈  V  ∧  𝐼  ∈  ( 𝒫  𝐵  ↑m  𝒫  𝐵 ) )  ∧  ( 𝑠  ∈  𝒫  𝐵  ∧  𝑡  ∈  𝒫  𝐵 ) )  →  𝐼  ∈  ( 𝒫  𝐵  ↑m  𝒫  𝐵 ) ) | 
						
							| 96 |  | eqid | ⊢ ( 𝐷 ‘ 𝐼 )  =  ( 𝐷 ‘ 𝐼 ) | 
						
							| 97 |  | simpl | ⊢ ( ( 𝐵  ∈  V  ∧  ( 𝑠  ∈  𝒫  𝐵  ∧  𝑡  ∈  𝒫  𝐵 ) )  →  𝐵  ∈  V ) | 
						
							| 98 |  | simprl | ⊢ ( ( 𝐵  ∈  V  ∧  ( 𝑠  ∈  𝒫  𝐵  ∧  𝑡  ∈  𝒫  𝐵 ) )  →  𝑠  ∈  𝒫  𝐵 ) | 
						
							| 99 | 98 | elpwid | ⊢ ( ( 𝐵  ∈  V  ∧  ( 𝑠  ∈  𝒫  𝐵  ∧  𝑡  ∈  𝒫  𝐵 ) )  →  𝑠  ⊆  𝐵 ) | 
						
							| 100 |  | simprr | ⊢ ( ( 𝐵  ∈  V  ∧  ( 𝑠  ∈  𝒫  𝐵  ∧  𝑡  ∈  𝒫  𝐵 ) )  →  𝑡  ∈  𝒫  𝐵 ) | 
						
							| 101 | 100 | elpwid | ⊢ ( ( 𝐵  ∈  V  ∧  ( 𝑠  ∈  𝒫  𝐵  ∧  𝑡  ∈  𝒫  𝐵 ) )  →  𝑡  ⊆  𝐵 ) | 
						
							| 102 | 99 101 | unssd | ⊢ ( ( 𝐵  ∈  V  ∧  ( 𝑠  ∈  𝒫  𝐵  ∧  𝑡  ∈  𝒫  𝐵 ) )  →  ( 𝑠  ∪  𝑡 )  ⊆  𝐵 ) | 
						
							| 103 | 97 102 | sselpwd | ⊢ ( ( 𝐵  ∈  V  ∧  ( 𝑠  ∈  𝒫  𝐵  ∧  𝑡  ∈  𝒫  𝐵 ) )  →  ( 𝑠  ∪  𝑡 )  ∈  𝒫  𝐵 ) | 
						
							| 104 | 103 | 3ad2antl2 | ⊢ ( ( ( 𝜑  ∧  𝐵  ∈  V  ∧  𝐼  ∈  ( 𝒫  𝐵  ↑m  𝒫  𝐵 ) )  ∧  ( 𝑠  ∈  𝒫  𝐵  ∧  𝑡  ∈  𝒫  𝐵 ) )  →  ( 𝑠  ∪  𝑡 )  ∈  𝒫  𝐵 ) | 
						
							| 105 |  | eqid | ⊢ ( ( 𝐷 ‘ 𝐼 ) ‘ ( 𝑠  ∪  𝑡 ) )  =  ( ( 𝐷 ‘ 𝐼 ) ‘ ( 𝑠  ∪  𝑡 ) ) | 
						
							| 106 | 1 2 94 95 96 104 105 | dssmapfv3d | ⊢ ( ( ( 𝜑  ∧  𝐵  ∈  V  ∧  𝐼  ∈  ( 𝒫  𝐵  ↑m  𝒫  𝐵 ) )  ∧  ( 𝑠  ∈  𝒫  𝐵  ∧  𝑡  ∈  𝒫  𝐵 ) )  →  ( ( 𝐷 ‘ 𝐼 ) ‘ ( 𝑠  ∪  𝑡 ) )  =  ( 𝐵  ∖  ( 𝐼 ‘ ( 𝐵  ∖  ( 𝑠  ∪  𝑡 ) ) ) ) ) | 
						
							| 107 |  | simpl1 | ⊢ ( ( ( 𝜑  ∧  𝐵  ∈  V  ∧  𝐼  ∈  ( 𝒫  𝐵  ↑m  𝒫  𝐵 ) )  ∧  ( 𝑠  ∈  𝒫  𝐵  ∧  𝑡  ∈  𝒫  𝐵 ) )  →  𝜑 ) | 
						
							| 108 | 1 2 3 | ntrclsfv1 | ⊢ ( 𝜑  →  ( 𝐷 ‘ 𝐼 )  =  𝐾 ) | 
						
							| 109 | 108 | fveq1d | ⊢ ( 𝜑  →  ( ( 𝐷 ‘ 𝐼 ) ‘ ( 𝑠  ∪  𝑡 ) )  =  ( 𝐾 ‘ ( 𝑠  ∪  𝑡 ) ) ) | 
						
							| 110 | 107 109 | syl | ⊢ ( ( ( 𝜑  ∧  𝐵  ∈  V  ∧  𝐼  ∈  ( 𝒫  𝐵  ↑m  𝒫  𝐵 ) )  ∧  ( 𝑠  ∈  𝒫  𝐵  ∧  𝑡  ∈  𝒫  𝐵 ) )  →  ( ( 𝐷 ‘ 𝐼 ) ‘ ( 𝑠  ∪  𝑡 ) )  =  ( 𝐾 ‘ ( 𝑠  ∪  𝑡 ) ) ) | 
						
							| 111 | 106 110 | eqtr3d | ⊢ ( ( ( 𝜑  ∧  𝐵  ∈  V  ∧  𝐼  ∈  ( 𝒫  𝐵  ↑m  𝒫  𝐵 ) )  ∧  ( 𝑠  ∈  𝒫  𝐵  ∧  𝑡  ∈  𝒫  𝐵 ) )  →  ( 𝐵  ∖  ( 𝐼 ‘ ( 𝐵  ∖  ( 𝑠  ∪  𝑡 ) ) ) )  =  ( 𝐾 ‘ ( 𝑠  ∪  𝑡 ) ) ) | 
						
							| 112 |  | simprl | ⊢ ( ( ( 𝜑  ∧  𝐵  ∈  V  ∧  𝐼  ∈  ( 𝒫  𝐵  ↑m  𝒫  𝐵 ) )  ∧  ( 𝑠  ∈  𝒫  𝐵  ∧  𝑡  ∈  𝒫  𝐵 ) )  →  𝑠  ∈  𝒫  𝐵 ) | 
						
							| 113 |  | eqid | ⊢ ( ( 𝐷 ‘ 𝐼 ) ‘ 𝑠 )  =  ( ( 𝐷 ‘ 𝐼 ) ‘ 𝑠 ) | 
						
							| 114 | 1 2 94 95 96 112 113 | dssmapfv3d | ⊢ ( ( ( 𝜑  ∧  𝐵  ∈  V  ∧  𝐼  ∈  ( 𝒫  𝐵  ↑m  𝒫  𝐵 ) )  ∧  ( 𝑠  ∈  𝒫  𝐵  ∧  𝑡  ∈  𝒫  𝐵 ) )  →  ( ( 𝐷 ‘ 𝐼 ) ‘ 𝑠 )  =  ( 𝐵  ∖  ( 𝐼 ‘ ( 𝐵  ∖  𝑠 ) ) ) ) | 
						
							| 115 | 108 | fveq1d | ⊢ ( 𝜑  →  ( ( 𝐷 ‘ 𝐼 ) ‘ 𝑠 )  =  ( 𝐾 ‘ 𝑠 ) ) | 
						
							| 116 | 107 115 | syl | ⊢ ( ( ( 𝜑  ∧  𝐵  ∈  V  ∧  𝐼  ∈  ( 𝒫  𝐵  ↑m  𝒫  𝐵 ) )  ∧  ( 𝑠  ∈  𝒫  𝐵  ∧  𝑡  ∈  𝒫  𝐵 ) )  →  ( ( 𝐷 ‘ 𝐼 ) ‘ 𝑠 )  =  ( 𝐾 ‘ 𝑠 ) ) | 
						
							| 117 | 114 116 | eqtr3d | ⊢ ( ( ( 𝜑  ∧  𝐵  ∈  V  ∧  𝐼  ∈  ( 𝒫  𝐵  ↑m  𝒫  𝐵 ) )  ∧  ( 𝑠  ∈  𝒫  𝐵  ∧  𝑡  ∈  𝒫  𝐵 ) )  →  ( 𝐵  ∖  ( 𝐼 ‘ ( 𝐵  ∖  𝑠 ) ) )  =  ( 𝐾 ‘ 𝑠 ) ) | 
						
							| 118 |  | simprr | ⊢ ( ( ( 𝜑  ∧  𝐵  ∈  V  ∧  𝐼  ∈  ( 𝒫  𝐵  ↑m  𝒫  𝐵 ) )  ∧  ( 𝑠  ∈  𝒫  𝐵  ∧  𝑡  ∈  𝒫  𝐵 ) )  →  𝑡  ∈  𝒫  𝐵 ) | 
						
							| 119 |  | eqid | ⊢ ( ( 𝐷 ‘ 𝐼 ) ‘ 𝑡 )  =  ( ( 𝐷 ‘ 𝐼 ) ‘ 𝑡 ) | 
						
							| 120 | 1 2 94 95 96 118 119 | dssmapfv3d | ⊢ ( ( ( 𝜑  ∧  𝐵  ∈  V  ∧  𝐼  ∈  ( 𝒫  𝐵  ↑m  𝒫  𝐵 ) )  ∧  ( 𝑠  ∈  𝒫  𝐵  ∧  𝑡  ∈  𝒫  𝐵 ) )  →  ( ( 𝐷 ‘ 𝐼 ) ‘ 𝑡 )  =  ( 𝐵  ∖  ( 𝐼 ‘ ( 𝐵  ∖  𝑡 ) ) ) ) | 
						
							| 121 | 108 | fveq1d | ⊢ ( 𝜑  →  ( ( 𝐷 ‘ 𝐼 ) ‘ 𝑡 )  =  ( 𝐾 ‘ 𝑡 ) ) | 
						
							| 122 | 107 121 | syl | ⊢ ( ( ( 𝜑  ∧  𝐵  ∈  V  ∧  𝐼  ∈  ( 𝒫  𝐵  ↑m  𝒫  𝐵 ) )  ∧  ( 𝑠  ∈  𝒫  𝐵  ∧  𝑡  ∈  𝒫  𝐵 ) )  →  ( ( 𝐷 ‘ 𝐼 ) ‘ 𝑡 )  =  ( 𝐾 ‘ 𝑡 ) ) | 
						
							| 123 | 120 122 | eqtr3d | ⊢ ( ( ( 𝜑  ∧  𝐵  ∈  V  ∧  𝐼  ∈  ( 𝒫  𝐵  ↑m  𝒫  𝐵 ) )  ∧  ( 𝑠  ∈  𝒫  𝐵  ∧  𝑡  ∈  𝒫  𝐵 ) )  →  ( 𝐵  ∖  ( 𝐼 ‘ ( 𝐵  ∖  𝑡 ) ) )  =  ( 𝐾 ‘ 𝑡 ) ) | 
						
							| 124 | 117 123 | uneq12d | ⊢ ( ( ( 𝜑  ∧  𝐵  ∈  V  ∧  𝐼  ∈  ( 𝒫  𝐵  ↑m  𝒫  𝐵 ) )  ∧  ( 𝑠  ∈  𝒫  𝐵  ∧  𝑡  ∈  𝒫  𝐵 ) )  →  ( ( 𝐵  ∖  ( 𝐼 ‘ ( 𝐵  ∖  𝑠 ) ) )  ∪  ( 𝐵  ∖  ( 𝐼 ‘ ( 𝐵  ∖  𝑡 ) ) ) )  =  ( ( 𝐾 ‘ 𝑠 )  ∪  ( 𝐾 ‘ 𝑡 ) ) ) | 
						
							| 125 | 111 124 | sseq12d | ⊢ ( ( ( 𝜑  ∧  𝐵  ∈  V  ∧  𝐼  ∈  ( 𝒫  𝐵  ↑m  𝒫  𝐵 ) )  ∧  ( 𝑠  ∈  𝒫  𝐵  ∧  𝑡  ∈  𝒫  𝐵 ) )  →  ( ( 𝐵  ∖  ( 𝐼 ‘ ( 𝐵  ∖  ( 𝑠  ∪  𝑡 ) ) ) )  ⊆  ( ( 𝐵  ∖  ( 𝐼 ‘ ( 𝐵  ∖  𝑠 ) ) )  ∪  ( 𝐵  ∖  ( 𝐼 ‘ ( 𝐵  ∖  𝑡 ) ) ) )  ↔  ( 𝐾 ‘ ( 𝑠  ∪  𝑡 ) )  ⊆  ( ( 𝐾 ‘ 𝑠 )  ∪  ( 𝐾 ‘ 𝑡 ) ) ) ) | 
						
							| 126 | 67 90 91 92 93 125 | syl32anc | ⊢ ( ( ( 𝜑  ∧  𝑠  ∈  𝒫  𝐵  ∧  𝑎  =  ( 𝐵  ∖  𝑠 ) )  ∧  𝑡  ∈  𝒫  𝐵  ∧  𝑏  =  ( 𝐵  ∖  𝑡 ) )  →  ( ( 𝐵  ∖  ( 𝐼 ‘ ( 𝐵  ∖  ( 𝑠  ∪  𝑡 ) ) ) )  ⊆  ( ( 𝐵  ∖  ( 𝐼 ‘ ( 𝐵  ∖  𝑠 ) ) )  ∪  ( 𝐵  ∖  ( 𝐼 ‘ ( 𝐵  ∖  𝑡 ) ) ) )  ↔  ( 𝐾 ‘ ( 𝑠  ∪  𝑡 ) )  ⊆  ( ( 𝐾 ‘ 𝑠 )  ∪  ( 𝐾 ‘ 𝑡 ) ) ) ) | 
						
							| 127 | 86 89 126 | 3bitrd | ⊢ ( ( ( 𝜑  ∧  𝑠  ∈  𝒫  𝐵  ∧  𝑎  =  ( 𝐵  ∖  𝑠 ) )  ∧  𝑡  ∈  𝒫  𝐵  ∧  𝑏  =  ( 𝐵  ∖  𝑡 ) )  →  ( ( ( 𝐼 ‘ ( 𝐵  ∖  𝑠 ) )  ∩  ( 𝐼 ‘ ( 𝐵  ∖  𝑡 ) ) )  ⊆  ( 𝐼 ‘ ( 𝐵  ∖  ( 𝑠  ∪  𝑡 ) ) )  ↔  ( 𝐾 ‘ ( 𝑠  ∪  𝑡 ) )  ⊆  ( ( 𝐾 ‘ 𝑠 )  ∪  ( 𝐾 ‘ 𝑡 ) ) ) ) | 
						
							| 128 | 58 66 127 | 3bitrd | ⊢ ( ( ( 𝜑  ∧  𝑠  ∈  𝒫  𝐵  ∧  𝑎  =  ( 𝐵  ∖  𝑠 ) )  ∧  𝑡  ∈  𝒫  𝐵  ∧  𝑏  =  ( 𝐵  ∖  𝑡 ) )  →  ( ( ( 𝐼 ‘ 𝑎 )  ∩  ( 𝐼 ‘ 𝑏 ) )  ⊆  ( 𝐼 ‘ ( 𝑎  ∩  𝑏 ) )  ↔  ( 𝐾 ‘ ( 𝑠  ∪  𝑡 ) )  ⊆  ( ( 𝐾 ‘ 𝑠 )  ∪  ( 𝐾 ‘ 𝑡 ) ) ) ) | 
						
							| 129 | 36 51 128 | ralxfrd2 | ⊢ ( ( 𝜑  ∧  𝑠  ∈  𝒫  𝐵  ∧  𝑎  =  ( 𝐵  ∖  𝑠 ) )  →  ( ∀ 𝑏  ∈  𝒫  𝐵 ( ( 𝐼 ‘ 𝑎 )  ∩  ( 𝐼 ‘ 𝑏 ) )  ⊆  ( 𝐼 ‘ ( 𝑎  ∩  𝑏 ) )  ↔  ∀ 𝑡  ∈  𝒫  𝐵 ( 𝐾 ‘ ( 𝑠  ∪  𝑡 ) )  ⊆  ( ( 𝐾 ‘ 𝑠 )  ∪  ( 𝐾 ‘ 𝑡 ) ) ) ) | 
						
							| 130 | 18 32 129 | ralxfrd2 | ⊢ ( 𝜑  →  ( ∀ 𝑎  ∈  𝒫  𝐵 ∀ 𝑏  ∈  𝒫  𝐵 ( ( 𝐼 ‘ 𝑎 )  ∩  ( 𝐼 ‘ 𝑏 ) )  ⊆  ( 𝐼 ‘ ( 𝑎  ∩  𝑏 ) )  ↔  ∀ 𝑠  ∈  𝒫  𝐵 ∀ 𝑡  ∈  𝒫  𝐵 ( 𝐾 ‘ ( 𝑠  ∪  𝑡 ) )  ⊆  ( ( 𝐾 ‘ 𝑠 )  ∪  ( 𝐾 ‘ 𝑡 ) ) ) ) | 
						
							| 131 | 14 130 | bitrid | ⊢ ( 𝜑  →  ( ∀ 𝑠  ∈  𝒫  𝐵 ∀ 𝑡  ∈  𝒫  𝐵 ( ( 𝐼 ‘ 𝑠 )  ∩  ( 𝐼 ‘ 𝑡 ) )  ⊆  ( 𝐼 ‘ ( 𝑠  ∩  𝑡 ) )  ↔  ∀ 𝑠  ∈  𝒫  𝐵 ∀ 𝑡  ∈  𝒫  𝐵 ( 𝐾 ‘ ( 𝑠  ∪  𝑡 ) )  ⊆  ( ( 𝐾 ‘ 𝑠 )  ∪  ( 𝐾 ‘ 𝑡 ) ) ) ) |