| Step | Hyp | Ref | Expression | 
						
							| 1 |  | clsk1indlem.k | ⊢ 𝐾  =  ( 𝑟  ∈  𝒫  3o  ↦  if ( 𝑟  =  { ∅ } ,  { ∅ ,  1o } ,  𝑟 ) ) | 
						
							| 2 |  | tpex | ⊢ { ∅ ,  1o ,  2o }  ∈  V | 
						
							| 3 |  | snsstp1 | ⊢ { ∅ }  ⊆  { ∅ ,  1o ,  2o } | 
						
							| 4 | 2 3 | elpwi2 | ⊢ { ∅ }  ∈  𝒫  { ∅ ,  1o ,  2o } | 
						
							| 5 |  | df3o2 | ⊢ 3o  =  { ∅ ,  1o ,  2o } | 
						
							| 6 | 5 | pweqi | ⊢ 𝒫  3o  =  𝒫  { ∅ ,  1o ,  2o } | 
						
							| 7 | 4 6 | eleqtrri | ⊢ { ∅ }  ∈  𝒫  3o | 
						
							| 8 | 2 | a1i | ⊢ ( ⊤  →  { ∅ ,  1o ,  2o }  ∈  V ) | 
						
							| 9 | 3 | a1i | ⊢ ( ⊤  →  { ∅ }  ⊆  { ∅ ,  1o ,  2o } ) | 
						
							| 10 |  | 0ex | ⊢ ∅  ∈  V | 
						
							| 11 | 10 | snss | ⊢ ( ∅  ∈  { ∅ ,  1o ,  2o }  ↔  { ∅ }  ⊆  { ∅ ,  1o ,  2o } ) | 
						
							| 12 | 9 11 | sylibr | ⊢ ( ⊤  →  ∅  ∈  { ∅ ,  1o ,  2o } ) | 
						
							| 13 |  | snsstp3 | ⊢ { 2o }  ⊆  { ∅ ,  1o ,  2o } | 
						
							| 14 | 13 | a1i | ⊢ ( ⊤  →  { 2o }  ⊆  { ∅ ,  1o ,  2o } ) | 
						
							| 15 |  | 2oex | ⊢ 2o  ∈  V | 
						
							| 16 | 15 | snss | ⊢ ( 2o  ∈  { ∅ ,  1o ,  2o }  ↔  { 2o }  ⊆  { ∅ ,  1o ,  2o } ) | 
						
							| 17 | 14 16 | sylibr | ⊢ ( ⊤  →  2o  ∈  { ∅ ,  1o ,  2o } ) | 
						
							| 18 | 12 17 | prssd | ⊢ ( ⊤  →  { ∅ ,  2o }  ⊆  { ∅ ,  1o ,  2o } ) | 
						
							| 19 | 8 18 | sselpwd | ⊢ ( ⊤  →  { ∅ ,  2o }  ∈  𝒫  { ∅ ,  1o ,  2o } ) | 
						
							| 20 | 19 | mptru | ⊢ { ∅ ,  2o }  ∈  𝒫  { ∅ ,  1o ,  2o } | 
						
							| 21 | 20 6 | eleqtrri | ⊢ { ∅ ,  2o }  ∈  𝒫  3o | 
						
							| 22 |  | simpl | ⊢ ( ( { ∅ }  ∈  𝒫  3o  ∧  { ∅ ,  2o }  ∈  𝒫  3o )  →  { ∅ }  ∈  𝒫  3o ) | 
						
							| 23 |  | sseq1 | ⊢ ( 𝑠  =  { ∅ }  →  ( 𝑠  ⊆  𝑡  ↔  { ∅ }  ⊆  𝑡 ) ) | 
						
							| 24 |  | fveq2 | ⊢ ( 𝑠  =  { ∅ }  →  ( 𝐾 ‘ 𝑠 )  =  ( 𝐾 ‘ { ∅ } ) ) | 
						
							| 25 | 24 | sseq1d | ⊢ ( 𝑠  =  { ∅ }  →  ( ( 𝐾 ‘ 𝑠 )  ⊆  ( 𝐾 ‘ 𝑡 )  ↔  ( 𝐾 ‘ { ∅ } )  ⊆  ( 𝐾 ‘ 𝑡 ) ) ) | 
						
							| 26 | 25 | notbid | ⊢ ( 𝑠  =  { ∅ }  →  ( ¬  ( 𝐾 ‘ 𝑠 )  ⊆  ( 𝐾 ‘ 𝑡 )  ↔  ¬  ( 𝐾 ‘ { ∅ } )  ⊆  ( 𝐾 ‘ 𝑡 ) ) ) | 
						
							| 27 | 23 26 | anbi12d | ⊢ ( 𝑠  =  { ∅ }  →  ( ( 𝑠  ⊆  𝑡  ∧  ¬  ( 𝐾 ‘ 𝑠 )  ⊆  ( 𝐾 ‘ 𝑡 ) )  ↔  ( { ∅ }  ⊆  𝑡  ∧  ¬  ( 𝐾 ‘ { ∅ } )  ⊆  ( 𝐾 ‘ 𝑡 ) ) ) ) | 
						
							| 28 | 27 | rexbidv | ⊢ ( 𝑠  =  { ∅ }  →  ( ∃ 𝑡  ∈  𝒫  3o ( 𝑠  ⊆  𝑡  ∧  ¬  ( 𝐾 ‘ 𝑠 )  ⊆  ( 𝐾 ‘ 𝑡 ) )  ↔  ∃ 𝑡  ∈  𝒫  3o ( { ∅ }  ⊆  𝑡  ∧  ¬  ( 𝐾 ‘ { ∅ } )  ⊆  ( 𝐾 ‘ 𝑡 ) ) ) ) | 
						
							| 29 | 28 | adantl | ⊢ ( ( ( { ∅ }  ∈  𝒫  3o  ∧  { ∅ ,  2o }  ∈  𝒫  3o )  ∧  𝑠  =  { ∅ } )  →  ( ∃ 𝑡  ∈  𝒫  3o ( 𝑠  ⊆  𝑡  ∧  ¬  ( 𝐾 ‘ 𝑠 )  ⊆  ( 𝐾 ‘ 𝑡 ) )  ↔  ∃ 𝑡  ∈  𝒫  3o ( { ∅ }  ⊆  𝑡  ∧  ¬  ( 𝐾 ‘ { ∅ } )  ⊆  ( 𝐾 ‘ 𝑡 ) ) ) ) | 
						
							| 30 |  | simpr | ⊢ ( ( { ∅ }  ∈  𝒫  3o  ∧  { ∅ ,  2o }  ∈  𝒫  3o )  →  { ∅ ,  2o }  ∈  𝒫  3o ) | 
						
							| 31 |  | fveq2 | ⊢ ( 𝑡  =  { ∅ ,  2o }  →  ( 𝐾 ‘ 𝑡 )  =  ( 𝐾 ‘ { ∅ ,  2o } ) ) | 
						
							| 32 | 31 | sseq2d | ⊢ ( 𝑡  =  { ∅ ,  2o }  →  ( ( 𝐾 ‘ { ∅ } )  ⊆  ( 𝐾 ‘ 𝑡 )  ↔  ( 𝐾 ‘ { ∅ } )  ⊆  ( 𝐾 ‘ { ∅ ,  2o } ) ) ) | 
						
							| 33 | 32 | notbid | ⊢ ( 𝑡  =  { ∅ ,  2o }  →  ( ¬  ( 𝐾 ‘ { ∅ } )  ⊆  ( 𝐾 ‘ 𝑡 )  ↔  ¬  ( 𝐾 ‘ { ∅ } )  ⊆  ( 𝐾 ‘ { ∅ ,  2o } ) ) ) | 
						
							| 34 | 33 | cleq2lem | ⊢ ( 𝑡  =  { ∅ ,  2o }  →  ( ( { ∅ }  ⊆  𝑡  ∧  ¬  ( 𝐾 ‘ { ∅ } )  ⊆  ( 𝐾 ‘ 𝑡 ) )  ↔  ( { ∅ }  ⊆  { ∅ ,  2o }  ∧  ¬  ( 𝐾 ‘ { ∅ } )  ⊆  ( 𝐾 ‘ { ∅ ,  2o } ) ) ) ) | 
						
							| 35 | 34 | adantl | ⊢ ( ( ( { ∅ }  ∈  𝒫  3o  ∧  { ∅ ,  2o }  ∈  𝒫  3o )  ∧  𝑡  =  { ∅ ,  2o } )  →  ( ( { ∅ }  ⊆  𝑡  ∧  ¬  ( 𝐾 ‘ { ∅ } )  ⊆  ( 𝐾 ‘ 𝑡 ) )  ↔  ( { ∅ }  ⊆  { ∅ ,  2o }  ∧  ¬  ( 𝐾 ‘ { ∅ } )  ⊆  ( 𝐾 ‘ { ∅ ,  2o } ) ) ) ) | 
						
							| 36 |  | 1oex | ⊢ 1o  ∈  V | 
						
							| 37 | 36 | prid2 | ⊢ 1o  ∈  { ∅ ,  1o } | 
						
							| 38 |  | iftrue | ⊢ ( 𝑟  =  { ∅ }  →  if ( 𝑟  =  { ∅ } ,  { ∅ ,  1o } ,  𝑟 )  =  { ∅ ,  1o } ) | 
						
							| 39 |  | prex | ⊢ { ∅ ,  1o }  ∈  V | 
						
							| 40 | 38 1 39 | fvmpt | ⊢ ( { ∅ }  ∈  𝒫  3o  →  ( 𝐾 ‘ { ∅ } )  =  { ∅ ,  1o } ) | 
						
							| 41 | 40 | adantr | ⊢ ( ( { ∅ }  ∈  𝒫  3o  ∧  { ∅ ,  2o }  ∈  𝒫  3o )  →  ( 𝐾 ‘ { ∅ } )  =  { ∅ ,  1o } ) | 
						
							| 42 | 37 41 | eleqtrrid | ⊢ ( ( { ∅ }  ∈  𝒫  3o  ∧  { ∅ ,  2o }  ∈  𝒫  3o )  →  1o  ∈  ( 𝐾 ‘ { ∅ } ) ) | 
						
							| 43 |  | 1n0 | ⊢ 1o  ≠  ∅ | 
						
							| 44 | 43 | neii | ⊢ ¬  1o  =  ∅ | 
						
							| 45 |  | eqcom | ⊢ ( 1o  =  2o  ↔  2o  =  1o ) | 
						
							| 46 |  | df-2o | ⊢ 2o  =  suc  1o | 
						
							| 47 |  | df-1o | ⊢ 1o  =  suc  ∅ | 
						
							| 48 | 46 47 | eqeq12i | ⊢ ( 2o  =  1o  ↔  suc  1o  =  suc  ∅ ) | 
						
							| 49 |  | suc11reg | ⊢ ( suc  1o  =  suc  ∅  ↔  1o  =  ∅ ) | 
						
							| 50 | 45 48 49 | 3bitri | ⊢ ( 1o  =  2o  ↔  1o  =  ∅ ) | 
						
							| 51 | 43 50 | nemtbir | ⊢ ¬  1o  =  2o | 
						
							| 52 | 44 51 | pm3.2ni | ⊢ ¬  ( 1o  =  ∅  ∨  1o  =  2o ) | 
						
							| 53 |  | elpri | ⊢ ( 1o  ∈  { ∅ ,  2o }  →  ( 1o  =  ∅  ∨  1o  =  2o ) ) | 
						
							| 54 | 52 53 | mto | ⊢ ¬  1o  ∈  { ∅ ,  2o } | 
						
							| 55 | 54 | a1i | ⊢ ( ( { ∅ }  ∈  𝒫  3o  ∧  { ∅ ,  2o }  ∈  𝒫  3o )  →  ¬  1o  ∈  { ∅ ,  2o } ) | 
						
							| 56 |  | eqeq1 | ⊢ ( 𝑟  =  { ∅ ,  2o }  →  ( 𝑟  =  { ∅ }  ↔  { ∅ ,  2o }  =  { ∅ } ) ) | 
						
							| 57 |  | id | ⊢ ( 𝑟  =  { ∅ ,  2o }  →  𝑟  =  { ∅ ,  2o } ) | 
						
							| 58 | 56 57 | ifbieq2d | ⊢ ( 𝑟  =  { ∅ ,  2o }  →  if ( 𝑟  =  { ∅ } ,  { ∅ ,  1o } ,  𝑟 )  =  if ( { ∅ ,  2o }  =  { ∅ } ,  { ∅ ,  1o } ,  { ∅ ,  2o } ) ) | 
						
							| 59 | 15 | prid2 | ⊢ 2o  ∈  { ∅ ,  2o } | 
						
							| 60 |  | 2on0 | ⊢ 2o  ≠  ∅ | 
						
							| 61 |  | nelsn | ⊢ ( 2o  ≠  ∅  →  ¬  2o  ∈  { ∅ } ) | 
						
							| 62 | 60 61 | ax-mp | ⊢ ¬  2o  ∈  { ∅ } | 
						
							| 63 |  | nelneq2 | ⊢ ( ( 2o  ∈  { ∅ ,  2o }  ∧  ¬  2o  ∈  { ∅ } )  →  ¬  { ∅ ,  2o }  =  { ∅ } ) | 
						
							| 64 | 59 62 63 | mp2an | ⊢ ¬  { ∅ ,  2o }  =  { ∅ } | 
						
							| 65 | 64 | iffalsei | ⊢ if ( { ∅ ,  2o }  =  { ∅ } ,  { ∅ ,  1o } ,  { ∅ ,  2o } )  =  { ∅ ,  2o } | 
						
							| 66 | 58 65 | eqtrdi | ⊢ ( 𝑟  =  { ∅ ,  2o }  →  if ( 𝑟  =  { ∅ } ,  { ∅ ,  1o } ,  𝑟 )  =  { ∅ ,  2o } ) | 
						
							| 67 |  | prex | ⊢ { ∅ ,  2o }  ∈  V | 
						
							| 68 | 66 1 67 | fvmpt | ⊢ ( { ∅ ,  2o }  ∈  𝒫  3o  →  ( 𝐾 ‘ { ∅ ,  2o } )  =  { ∅ ,  2o } ) | 
						
							| 69 | 68 | adantl | ⊢ ( ( { ∅ }  ∈  𝒫  3o  ∧  { ∅ ,  2o }  ∈  𝒫  3o )  →  ( 𝐾 ‘ { ∅ ,  2o } )  =  { ∅ ,  2o } ) | 
						
							| 70 | 55 69 | neleqtrrd | ⊢ ( ( { ∅ }  ∈  𝒫  3o  ∧  { ∅ ,  2o }  ∈  𝒫  3o )  →  ¬  1o  ∈  ( 𝐾 ‘ { ∅ ,  2o } ) ) | 
						
							| 71 |  | nelss | ⊢ ( ( 1o  ∈  ( 𝐾 ‘ { ∅ } )  ∧  ¬  1o  ∈  ( 𝐾 ‘ { ∅ ,  2o } ) )  →  ¬  ( 𝐾 ‘ { ∅ } )  ⊆  ( 𝐾 ‘ { ∅ ,  2o } ) ) | 
						
							| 72 | 42 70 71 | syl2anc | ⊢ ( ( { ∅ }  ∈  𝒫  3o  ∧  { ∅ ,  2o }  ∈  𝒫  3o )  →  ¬  ( 𝐾 ‘ { ∅ } )  ⊆  ( 𝐾 ‘ { ∅ ,  2o } ) ) | 
						
							| 73 |  | snsspr1 | ⊢ { ∅ }  ⊆  { ∅ ,  2o } | 
						
							| 74 | 72 73 | jctil | ⊢ ( ( { ∅ }  ∈  𝒫  3o  ∧  { ∅ ,  2o }  ∈  𝒫  3o )  →  ( { ∅ }  ⊆  { ∅ ,  2o }  ∧  ¬  ( 𝐾 ‘ { ∅ } )  ⊆  ( 𝐾 ‘ { ∅ ,  2o } ) ) ) | 
						
							| 75 | 30 35 74 | rspcedvd | ⊢ ( ( { ∅ }  ∈  𝒫  3o  ∧  { ∅ ,  2o }  ∈  𝒫  3o )  →  ∃ 𝑡  ∈  𝒫  3o ( { ∅ }  ⊆  𝑡  ∧  ¬  ( 𝐾 ‘ { ∅ } )  ⊆  ( 𝐾 ‘ 𝑡 ) ) ) | 
						
							| 76 | 22 29 75 | rspcedvd | ⊢ ( ( { ∅ }  ∈  𝒫  3o  ∧  { ∅ ,  2o }  ∈  𝒫  3o )  →  ∃ 𝑠  ∈  𝒫  3o ∃ 𝑡  ∈  𝒫  3o ( 𝑠  ⊆  𝑡  ∧  ¬  ( 𝐾 ‘ 𝑠 )  ⊆  ( 𝐾 ‘ 𝑡 ) ) ) | 
						
							| 77 | 7 21 76 | mp2an | ⊢ ∃ 𝑠  ∈  𝒫  3o ∃ 𝑡  ∈  𝒫  3o ( 𝑠  ⊆  𝑡  ∧  ¬  ( 𝐾 ‘ 𝑠 )  ⊆  ( 𝐾 ‘ 𝑡 ) ) |