| Step | Hyp | Ref | Expression | 
						
							| 1 |  | oveq2 | ⊢ ( 𝑥  =  suc  𝐴  →  ( 𝐶  ↑o  𝑥 )  =  ( 𝐶  ↑o  suc  𝐴 ) ) | 
						
							| 2 | 1 | eleq2d | ⊢ ( 𝑥  =  suc  𝐴  →  ( ( 𝐶  ↑o  𝐴 )  ∈  ( 𝐶  ↑o  𝑥 )  ↔  ( 𝐶  ↑o  𝐴 )  ∈  ( 𝐶  ↑o  suc  𝐴 ) ) ) | 
						
							| 3 | 2 | imbi2d | ⊢ ( 𝑥  =  suc  𝐴  →  ( ( 𝐶  ∈  ( On  ∖  2o )  →  ( 𝐶  ↑o  𝐴 )  ∈  ( 𝐶  ↑o  𝑥 ) )  ↔  ( 𝐶  ∈  ( On  ∖  2o )  →  ( 𝐶  ↑o  𝐴 )  ∈  ( 𝐶  ↑o  suc  𝐴 ) ) ) ) | 
						
							| 4 |  | oveq2 | ⊢ ( 𝑥  =  𝑦  →  ( 𝐶  ↑o  𝑥 )  =  ( 𝐶  ↑o  𝑦 ) ) | 
						
							| 5 | 4 | eleq2d | ⊢ ( 𝑥  =  𝑦  →  ( ( 𝐶  ↑o  𝐴 )  ∈  ( 𝐶  ↑o  𝑥 )  ↔  ( 𝐶  ↑o  𝐴 )  ∈  ( 𝐶  ↑o  𝑦 ) ) ) | 
						
							| 6 | 5 | imbi2d | ⊢ ( 𝑥  =  𝑦  →  ( ( 𝐶  ∈  ( On  ∖  2o )  →  ( 𝐶  ↑o  𝐴 )  ∈  ( 𝐶  ↑o  𝑥 ) )  ↔  ( 𝐶  ∈  ( On  ∖  2o )  →  ( 𝐶  ↑o  𝐴 )  ∈  ( 𝐶  ↑o  𝑦 ) ) ) ) | 
						
							| 7 |  | oveq2 | ⊢ ( 𝑥  =  suc  𝑦  →  ( 𝐶  ↑o  𝑥 )  =  ( 𝐶  ↑o  suc  𝑦 ) ) | 
						
							| 8 | 7 | eleq2d | ⊢ ( 𝑥  =  suc  𝑦  →  ( ( 𝐶  ↑o  𝐴 )  ∈  ( 𝐶  ↑o  𝑥 )  ↔  ( 𝐶  ↑o  𝐴 )  ∈  ( 𝐶  ↑o  suc  𝑦 ) ) ) | 
						
							| 9 | 8 | imbi2d | ⊢ ( 𝑥  =  suc  𝑦  →  ( ( 𝐶  ∈  ( On  ∖  2o )  →  ( 𝐶  ↑o  𝐴 )  ∈  ( 𝐶  ↑o  𝑥 ) )  ↔  ( 𝐶  ∈  ( On  ∖  2o )  →  ( 𝐶  ↑o  𝐴 )  ∈  ( 𝐶  ↑o  suc  𝑦 ) ) ) ) | 
						
							| 10 |  | oveq2 | ⊢ ( 𝑥  =  𝐵  →  ( 𝐶  ↑o  𝑥 )  =  ( 𝐶  ↑o  𝐵 ) ) | 
						
							| 11 | 10 | eleq2d | ⊢ ( 𝑥  =  𝐵  →  ( ( 𝐶  ↑o  𝐴 )  ∈  ( 𝐶  ↑o  𝑥 )  ↔  ( 𝐶  ↑o  𝐴 )  ∈  ( 𝐶  ↑o  𝐵 ) ) ) | 
						
							| 12 | 11 | imbi2d | ⊢ ( 𝑥  =  𝐵  →  ( ( 𝐶  ∈  ( On  ∖  2o )  →  ( 𝐶  ↑o  𝐴 )  ∈  ( 𝐶  ↑o  𝑥 ) )  ↔  ( 𝐶  ∈  ( On  ∖  2o )  →  ( 𝐶  ↑o  𝐴 )  ∈  ( 𝐶  ↑o  𝐵 ) ) ) ) | 
						
							| 13 |  | eldifi | ⊢ ( 𝐶  ∈  ( On  ∖  2o )  →  𝐶  ∈  On ) | 
						
							| 14 |  | oecl | ⊢ ( ( 𝐶  ∈  On  ∧  𝐴  ∈  On )  →  ( 𝐶  ↑o  𝐴 )  ∈  On ) | 
						
							| 15 | 13 14 | sylan | ⊢ ( ( 𝐶  ∈  ( On  ∖  2o )  ∧  𝐴  ∈  On )  →  ( 𝐶  ↑o  𝐴 )  ∈  On ) | 
						
							| 16 |  | om1 | ⊢ ( ( 𝐶  ↑o  𝐴 )  ∈  On  →  ( ( 𝐶  ↑o  𝐴 )  ·o  1o )  =  ( 𝐶  ↑o  𝐴 ) ) | 
						
							| 17 | 15 16 | syl | ⊢ ( ( 𝐶  ∈  ( On  ∖  2o )  ∧  𝐴  ∈  On )  →  ( ( 𝐶  ↑o  𝐴 )  ·o  1o )  =  ( 𝐶  ↑o  𝐴 ) ) | 
						
							| 18 |  | ondif2 | ⊢ ( 𝐶  ∈  ( On  ∖  2o )  ↔  ( 𝐶  ∈  On  ∧  1o  ∈  𝐶 ) ) | 
						
							| 19 | 18 | simprbi | ⊢ ( 𝐶  ∈  ( On  ∖  2o )  →  1o  ∈  𝐶 ) | 
						
							| 20 | 19 | adantr | ⊢ ( ( 𝐶  ∈  ( On  ∖  2o )  ∧  𝐴  ∈  On )  →  1o  ∈  𝐶 ) | 
						
							| 21 | 13 | adantr | ⊢ ( ( 𝐶  ∈  ( On  ∖  2o )  ∧  𝐴  ∈  On )  →  𝐶  ∈  On ) | 
						
							| 22 |  | simpr | ⊢ ( ( 𝐶  ∈  ( On  ∖  2o )  ∧  𝐴  ∈  On )  →  𝐴  ∈  On ) | 
						
							| 23 |  | dif20el | ⊢ ( 𝐶  ∈  ( On  ∖  2o )  →  ∅  ∈  𝐶 ) | 
						
							| 24 | 23 | adantr | ⊢ ( ( 𝐶  ∈  ( On  ∖  2o )  ∧  𝐴  ∈  On )  →  ∅  ∈  𝐶 ) | 
						
							| 25 |  | oen0 | ⊢ ( ( ( 𝐶  ∈  On  ∧  𝐴  ∈  On )  ∧  ∅  ∈  𝐶 )  →  ∅  ∈  ( 𝐶  ↑o  𝐴 ) ) | 
						
							| 26 | 21 22 24 25 | syl21anc | ⊢ ( ( 𝐶  ∈  ( On  ∖  2o )  ∧  𝐴  ∈  On )  →  ∅  ∈  ( 𝐶  ↑o  𝐴 ) ) | 
						
							| 27 |  | omordi | ⊢ ( ( ( 𝐶  ∈  On  ∧  ( 𝐶  ↑o  𝐴 )  ∈  On )  ∧  ∅  ∈  ( 𝐶  ↑o  𝐴 ) )  →  ( 1o  ∈  𝐶  →  ( ( 𝐶  ↑o  𝐴 )  ·o  1o )  ∈  ( ( 𝐶  ↑o  𝐴 )  ·o  𝐶 ) ) ) | 
						
							| 28 | 21 15 26 27 | syl21anc | ⊢ ( ( 𝐶  ∈  ( On  ∖  2o )  ∧  𝐴  ∈  On )  →  ( 1o  ∈  𝐶  →  ( ( 𝐶  ↑o  𝐴 )  ·o  1o )  ∈  ( ( 𝐶  ↑o  𝐴 )  ·o  𝐶 ) ) ) | 
						
							| 29 | 20 28 | mpd | ⊢ ( ( 𝐶  ∈  ( On  ∖  2o )  ∧  𝐴  ∈  On )  →  ( ( 𝐶  ↑o  𝐴 )  ·o  1o )  ∈  ( ( 𝐶  ↑o  𝐴 )  ·o  𝐶 ) ) | 
						
							| 30 | 17 29 | eqeltrrd | ⊢ ( ( 𝐶  ∈  ( On  ∖  2o )  ∧  𝐴  ∈  On )  →  ( 𝐶  ↑o  𝐴 )  ∈  ( ( 𝐶  ↑o  𝐴 )  ·o  𝐶 ) ) | 
						
							| 31 |  | oesuc | ⊢ ( ( 𝐶  ∈  On  ∧  𝐴  ∈  On )  →  ( 𝐶  ↑o  suc  𝐴 )  =  ( ( 𝐶  ↑o  𝐴 )  ·o  𝐶 ) ) | 
						
							| 32 | 13 31 | sylan | ⊢ ( ( 𝐶  ∈  ( On  ∖  2o )  ∧  𝐴  ∈  On )  →  ( 𝐶  ↑o  suc  𝐴 )  =  ( ( 𝐶  ↑o  𝐴 )  ·o  𝐶 ) ) | 
						
							| 33 | 30 32 | eleqtrrd | ⊢ ( ( 𝐶  ∈  ( On  ∖  2o )  ∧  𝐴  ∈  On )  →  ( 𝐶  ↑o  𝐴 )  ∈  ( 𝐶  ↑o  suc  𝐴 ) ) | 
						
							| 34 | 33 | expcom | ⊢ ( 𝐴  ∈  On  →  ( 𝐶  ∈  ( On  ∖  2o )  →  ( 𝐶  ↑o  𝐴 )  ∈  ( 𝐶  ↑o  suc  𝐴 ) ) ) | 
						
							| 35 |  | oecl | ⊢ ( ( 𝐶  ∈  On  ∧  𝑦  ∈  On )  →  ( 𝐶  ↑o  𝑦 )  ∈  On ) | 
						
							| 36 | 13 35 | sylan | ⊢ ( ( 𝐶  ∈  ( On  ∖  2o )  ∧  𝑦  ∈  On )  →  ( 𝐶  ↑o  𝑦 )  ∈  On ) | 
						
							| 37 |  | om1 | ⊢ ( ( 𝐶  ↑o  𝑦 )  ∈  On  →  ( ( 𝐶  ↑o  𝑦 )  ·o  1o )  =  ( 𝐶  ↑o  𝑦 ) ) | 
						
							| 38 | 36 37 | syl | ⊢ ( ( 𝐶  ∈  ( On  ∖  2o )  ∧  𝑦  ∈  On )  →  ( ( 𝐶  ↑o  𝑦 )  ·o  1o )  =  ( 𝐶  ↑o  𝑦 ) ) | 
						
							| 39 | 19 | adantr | ⊢ ( ( 𝐶  ∈  ( On  ∖  2o )  ∧  𝑦  ∈  On )  →  1o  ∈  𝐶 ) | 
						
							| 40 | 13 | adantr | ⊢ ( ( 𝐶  ∈  ( On  ∖  2o )  ∧  𝑦  ∈  On )  →  𝐶  ∈  On ) | 
						
							| 41 |  | simpr | ⊢ ( ( 𝐶  ∈  ( On  ∖  2o )  ∧  𝑦  ∈  On )  →  𝑦  ∈  On ) | 
						
							| 42 | 23 | adantr | ⊢ ( ( 𝐶  ∈  ( On  ∖  2o )  ∧  𝑦  ∈  On )  →  ∅  ∈  𝐶 ) | 
						
							| 43 |  | oen0 | ⊢ ( ( ( 𝐶  ∈  On  ∧  𝑦  ∈  On )  ∧  ∅  ∈  𝐶 )  →  ∅  ∈  ( 𝐶  ↑o  𝑦 ) ) | 
						
							| 44 | 40 41 42 43 | syl21anc | ⊢ ( ( 𝐶  ∈  ( On  ∖  2o )  ∧  𝑦  ∈  On )  →  ∅  ∈  ( 𝐶  ↑o  𝑦 ) ) | 
						
							| 45 |  | omordi | ⊢ ( ( ( 𝐶  ∈  On  ∧  ( 𝐶  ↑o  𝑦 )  ∈  On )  ∧  ∅  ∈  ( 𝐶  ↑o  𝑦 ) )  →  ( 1o  ∈  𝐶  →  ( ( 𝐶  ↑o  𝑦 )  ·o  1o )  ∈  ( ( 𝐶  ↑o  𝑦 )  ·o  𝐶 ) ) ) | 
						
							| 46 | 40 36 44 45 | syl21anc | ⊢ ( ( 𝐶  ∈  ( On  ∖  2o )  ∧  𝑦  ∈  On )  →  ( 1o  ∈  𝐶  →  ( ( 𝐶  ↑o  𝑦 )  ·o  1o )  ∈  ( ( 𝐶  ↑o  𝑦 )  ·o  𝐶 ) ) ) | 
						
							| 47 | 39 46 | mpd | ⊢ ( ( 𝐶  ∈  ( On  ∖  2o )  ∧  𝑦  ∈  On )  →  ( ( 𝐶  ↑o  𝑦 )  ·o  1o )  ∈  ( ( 𝐶  ↑o  𝑦 )  ·o  𝐶 ) ) | 
						
							| 48 | 38 47 | eqeltrrd | ⊢ ( ( 𝐶  ∈  ( On  ∖  2o )  ∧  𝑦  ∈  On )  →  ( 𝐶  ↑o  𝑦 )  ∈  ( ( 𝐶  ↑o  𝑦 )  ·o  𝐶 ) ) | 
						
							| 49 |  | oesuc | ⊢ ( ( 𝐶  ∈  On  ∧  𝑦  ∈  On )  →  ( 𝐶  ↑o  suc  𝑦 )  =  ( ( 𝐶  ↑o  𝑦 )  ·o  𝐶 ) ) | 
						
							| 50 | 13 49 | sylan | ⊢ ( ( 𝐶  ∈  ( On  ∖  2o )  ∧  𝑦  ∈  On )  →  ( 𝐶  ↑o  suc  𝑦 )  =  ( ( 𝐶  ↑o  𝑦 )  ·o  𝐶 ) ) | 
						
							| 51 | 48 50 | eleqtrrd | ⊢ ( ( 𝐶  ∈  ( On  ∖  2o )  ∧  𝑦  ∈  On )  →  ( 𝐶  ↑o  𝑦 )  ∈  ( 𝐶  ↑o  suc  𝑦 ) ) | 
						
							| 52 |  | onsuc | ⊢ ( 𝑦  ∈  On  →  suc  𝑦  ∈  On ) | 
						
							| 53 |  | oecl | ⊢ ( ( 𝐶  ∈  On  ∧  suc  𝑦  ∈  On )  →  ( 𝐶  ↑o  suc  𝑦 )  ∈  On ) | 
						
							| 54 | 13 52 53 | syl2an | ⊢ ( ( 𝐶  ∈  ( On  ∖  2o )  ∧  𝑦  ∈  On )  →  ( 𝐶  ↑o  suc  𝑦 )  ∈  On ) | 
						
							| 55 |  | ontr1 | ⊢ ( ( 𝐶  ↑o  suc  𝑦 )  ∈  On  →  ( ( ( 𝐶  ↑o  𝐴 )  ∈  ( 𝐶  ↑o  𝑦 )  ∧  ( 𝐶  ↑o  𝑦 )  ∈  ( 𝐶  ↑o  suc  𝑦 ) )  →  ( 𝐶  ↑o  𝐴 )  ∈  ( 𝐶  ↑o  suc  𝑦 ) ) ) | 
						
							| 56 | 54 55 | syl | ⊢ ( ( 𝐶  ∈  ( On  ∖  2o )  ∧  𝑦  ∈  On )  →  ( ( ( 𝐶  ↑o  𝐴 )  ∈  ( 𝐶  ↑o  𝑦 )  ∧  ( 𝐶  ↑o  𝑦 )  ∈  ( 𝐶  ↑o  suc  𝑦 ) )  →  ( 𝐶  ↑o  𝐴 )  ∈  ( 𝐶  ↑o  suc  𝑦 ) ) ) | 
						
							| 57 | 51 56 | mpan2d | ⊢ ( ( 𝐶  ∈  ( On  ∖  2o )  ∧  𝑦  ∈  On )  →  ( ( 𝐶  ↑o  𝐴 )  ∈  ( 𝐶  ↑o  𝑦 )  →  ( 𝐶  ↑o  𝐴 )  ∈  ( 𝐶  ↑o  suc  𝑦 ) ) ) | 
						
							| 58 | 57 | expcom | ⊢ ( 𝑦  ∈  On  →  ( 𝐶  ∈  ( On  ∖  2o )  →  ( ( 𝐶  ↑o  𝐴 )  ∈  ( 𝐶  ↑o  𝑦 )  →  ( 𝐶  ↑o  𝐴 )  ∈  ( 𝐶  ↑o  suc  𝑦 ) ) ) ) | 
						
							| 59 | 58 | adantr | ⊢ ( ( 𝑦  ∈  On  ∧  𝐴  ∈  𝑦 )  →  ( 𝐶  ∈  ( On  ∖  2o )  →  ( ( 𝐶  ↑o  𝐴 )  ∈  ( 𝐶  ↑o  𝑦 )  →  ( 𝐶  ↑o  𝐴 )  ∈  ( 𝐶  ↑o  suc  𝑦 ) ) ) ) | 
						
							| 60 | 59 | a2d | ⊢ ( ( 𝑦  ∈  On  ∧  𝐴  ∈  𝑦 )  →  ( ( 𝐶  ∈  ( On  ∖  2o )  →  ( 𝐶  ↑o  𝐴 )  ∈  ( 𝐶  ↑o  𝑦 ) )  →  ( 𝐶  ∈  ( On  ∖  2o )  →  ( 𝐶  ↑o  𝐴 )  ∈  ( 𝐶  ↑o  suc  𝑦 ) ) ) ) | 
						
							| 61 |  | bi2.04 | ⊢ ( ( 𝐴  ∈  𝑦  →  ( 𝐶  ∈  ( On  ∖  2o )  →  ( 𝐶  ↑o  𝐴 )  ∈  ( 𝐶  ↑o  𝑦 ) ) )  ↔  ( 𝐶  ∈  ( On  ∖  2o )  →  ( 𝐴  ∈  𝑦  →  ( 𝐶  ↑o  𝐴 )  ∈  ( 𝐶  ↑o  𝑦 ) ) ) ) | 
						
							| 62 | 61 | ralbii | ⊢ ( ∀ 𝑦  ∈  𝑥 ( 𝐴  ∈  𝑦  →  ( 𝐶  ∈  ( On  ∖  2o )  →  ( 𝐶  ↑o  𝐴 )  ∈  ( 𝐶  ↑o  𝑦 ) ) )  ↔  ∀ 𝑦  ∈  𝑥 ( 𝐶  ∈  ( On  ∖  2o )  →  ( 𝐴  ∈  𝑦  →  ( 𝐶  ↑o  𝐴 )  ∈  ( 𝐶  ↑o  𝑦 ) ) ) ) | 
						
							| 63 |  | r19.21v | ⊢ ( ∀ 𝑦  ∈  𝑥 ( 𝐶  ∈  ( On  ∖  2o )  →  ( 𝐴  ∈  𝑦  →  ( 𝐶  ↑o  𝐴 )  ∈  ( 𝐶  ↑o  𝑦 ) ) )  ↔  ( 𝐶  ∈  ( On  ∖  2o )  →  ∀ 𝑦  ∈  𝑥 ( 𝐴  ∈  𝑦  →  ( 𝐶  ↑o  𝐴 )  ∈  ( 𝐶  ↑o  𝑦 ) ) ) ) | 
						
							| 64 | 62 63 | bitri | ⊢ ( ∀ 𝑦  ∈  𝑥 ( 𝐴  ∈  𝑦  →  ( 𝐶  ∈  ( On  ∖  2o )  →  ( 𝐶  ↑o  𝐴 )  ∈  ( 𝐶  ↑o  𝑦 ) ) )  ↔  ( 𝐶  ∈  ( On  ∖  2o )  →  ∀ 𝑦  ∈  𝑥 ( 𝐴  ∈  𝑦  →  ( 𝐶  ↑o  𝐴 )  ∈  ( 𝐶  ↑o  𝑦 ) ) ) ) | 
						
							| 65 |  | limsuc | ⊢ ( Lim  𝑥  →  ( 𝐴  ∈  𝑥  ↔  suc  𝐴  ∈  𝑥 ) ) | 
						
							| 66 | 65 | biimpa | ⊢ ( ( Lim  𝑥  ∧  𝐴  ∈  𝑥 )  →  suc  𝐴  ∈  𝑥 ) | 
						
							| 67 |  | elex | ⊢ ( suc  𝐴  ∈  𝑥  →  suc  𝐴  ∈  V ) | 
						
							| 68 |  | sucexb | ⊢ ( 𝐴  ∈  V  ↔  suc  𝐴  ∈  V ) | 
						
							| 69 |  | sucidg | ⊢ ( 𝐴  ∈  V  →  𝐴  ∈  suc  𝐴 ) | 
						
							| 70 | 68 69 | sylbir | ⊢ ( suc  𝐴  ∈  V  →  𝐴  ∈  suc  𝐴 ) | 
						
							| 71 | 67 70 | syl | ⊢ ( suc  𝐴  ∈  𝑥  →  𝐴  ∈  suc  𝐴 ) | 
						
							| 72 |  | eleq2 | ⊢ ( 𝑦  =  suc  𝐴  →  ( 𝐴  ∈  𝑦  ↔  𝐴  ∈  suc  𝐴 ) ) | 
						
							| 73 |  | oveq2 | ⊢ ( 𝑦  =  suc  𝐴  →  ( 𝐶  ↑o  𝑦 )  =  ( 𝐶  ↑o  suc  𝐴 ) ) | 
						
							| 74 | 73 | eleq2d | ⊢ ( 𝑦  =  suc  𝐴  →  ( ( 𝐶  ↑o  𝐴 )  ∈  ( 𝐶  ↑o  𝑦 )  ↔  ( 𝐶  ↑o  𝐴 )  ∈  ( 𝐶  ↑o  suc  𝐴 ) ) ) | 
						
							| 75 | 72 74 | imbi12d | ⊢ ( 𝑦  =  suc  𝐴  →  ( ( 𝐴  ∈  𝑦  →  ( 𝐶  ↑o  𝐴 )  ∈  ( 𝐶  ↑o  𝑦 ) )  ↔  ( 𝐴  ∈  suc  𝐴  →  ( 𝐶  ↑o  𝐴 )  ∈  ( 𝐶  ↑o  suc  𝐴 ) ) ) ) | 
						
							| 76 | 75 | rspcv | ⊢ ( suc  𝐴  ∈  𝑥  →  ( ∀ 𝑦  ∈  𝑥 ( 𝐴  ∈  𝑦  →  ( 𝐶  ↑o  𝐴 )  ∈  ( 𝐶  ↑o  𝑦 ) )  →  ( 𝐴  ∈  suc  𝐴  →  ( 𝐶  ↑o  𝐴 )  ∈  ( 𝐶  ↑o  suc  𝐴 ) ) ) ) | 
						
							| 77 | 71 76 | mpid | ⊢ ( suc  𝐴  ∈  𝑥  →  ( ∀ 𝑦  ∈  𝑥 ( 𝐴  ∈  𝑦  →  ( 𝐶  ↑o  𝐴 )  ∈  ( 𝐶  ↑o  𝑦 ) )  →  ( 𝐶  ↑o  𝐴 )  ∈  ( 𝐶  ↑o  suc  𝐴 ) ) ) | 
						
							| 78 | 77 | anc2li | ⊢ ( suc  𝐴  ∈  𝑥  →  ( ∀ 𝑦  ∈  𝑥 ( 𝐴  ∈  𝑦  →  ( 𝐶  ↑o  𝐴 )  ∈  ( 𝐶  ↑o  𝑦 ) )  →  ( suc  𝐴  ∈  𝑥  ∧  ( 𝐶  ↑o  𝐴 )  ∈  ( 𝐶  ↑o  suc  𝐴 ) ) ) ) | 
						
							| 79 | 73 | eliuni | ⊢ ( ( suc  𝐴  ∈  𝑥  ∧  ( 𝐶  ↑o  𝐴 )  ∈  ( 𝐶  ↑o  suc  𝐴 ) )  →  ( 𝐶  ↑o  𝐴 )  ∈  ∪  𝑦  ∈  𝑥 ( 𝐶  ↑o  𝑦 ) ) | 
						
							| 80 | 78 79 | syl6 | ⊢ ( suc  𝐴  ∈  𝑥  →  ( ∀ 𝑦  ∈  𝑥 ( 𝐴  ∈  𝑦  →  ( 𝐶  ↑o  𝐴 )  ∈  ( 𝐶  ↑o  𝑦 ) )  →  ( 𝐶  ↑o  𝐴 )  ∈  ∪  𝑦  ∈  𝑥 ( 𝐶  ↑o  𝑦 ) ) ) | 
						
							| 81 | 66 80 | syl | ⊢ ( ( Lim  𝑥  ∧  𝐴  ∈  𝑥 )  →  ( ∀ 𝑦  ∈  𝑥 ( 𝐴  ∈  𝑦  →  ( 𝐶  ↑o  𝐴 )  ∈  ( 𝐶  ↑o  𝑦 ) )  →  ( 𝐶  ↑o  𝐴 )  ∈  ∪  𝑦  ∈  𝑥 ( 𝐶  ↑o  𝑦 ) ) ) | 
						
							| 82 | 81 | adantr | ⊢ ( ( ( Lim  𝑥  ∧  𝐴  ∈  𝑥 )  ∧  𝐶  ∈  ( On  ∖  2o ) )  →  ( ∀ 𝑦  ∈  𝑥 ( 𝐴  ∈  𝑦  →  ( 𝐶  ↑o  𝐴 )  ∈  ( 𝐶  ↑o  𝑦 ) )  →  ( 𝐶  ↑o  𝐴 )  ∈  ∪  𝑦  ∈  𝑥 ( 𝐶  ↑o  𝑦 ) ) ) | 
						
							| 83 | 13 | adantl | ⊢ ( ( Lim  𝑥  ∧  𝐶  ∈  ( On  ∖  2o ) )  →  𝐶  ∈  On ) | 
						
							| 84 |  | simpl | ⊢ ( ( Lim  𝑥  ∧  𝐶  ∈  ( On  ∖  2o ) )  →  Lim  𝑥 ) | 
						
							| 85 | 23 | adantl | ⊢ ( ( Lim  𝑥  ∧  𝐶  ∈  ( On  ∖  2o ) )  →  ∅  ∈  𝐶 ) | 
						
							| 86 |  | vex | ⊢ 𝑥  ∈  V | 
						
							| 87 |  | oelim | ⊢ ( ( ( 𝐶  ∈  On  ∧  ( 𝑥  ∈  V  ∧  Lim  𝑥 ) )  ∧  ∅  ∈  𝐶 )  →  ( 𝐶  ↑o  𝑥 )  =  ∪  𝑦  ∈  𝑥 ( 𝐶  ↑o  𝑦 ) ) | 
						
							| 88 | 86 87 | mpanlr1 | ⊢ ( ( ( 𝐶  ∈  On  ∧  Lim  𝑥 )  ∧  ∅  ∈  𝐶 )  →  ( 𝐶  ↑o  𝑥 )  =  ∪  𝑦  ∈  𝑥 ( 𝐶  ↑o  𝑦 ) ) | 
						
							| 89 | 83 84 85 88 | syl21anc | ⊢ ( ( Lim  𝑥  ∧  𝐶  ∈  ( On  ∖  2o ) )  →  ( 𝐶  ↑o  𝑥 )  =  ∪  𝑦  ∈  𝑥 ( 𝐶  ↑o  𝑦 ) ) | 
						
							| 90 | 89 | adantlr | ⊢ ( ( ( Lim  𝑥  ∧  𝐴  ∈  𝑥 )  ∧  𝐶  ∈  ( On  ∖  2o ) )  →  ( 𝐶  ↑o  𝑥 )  =  ∪  𝑦  ∈  𝑥 ( 𝐶  ↑o  𝑦 ) ) | 
						
							| 91 | 90 | eleq2d | ⊢ ( ( ( Lim  𝑥  ∧  𝐴  ∈  𝑥 )  ∧  𝐶  ∈  ( On  ∖  2o ) )  →  ( ( 𝐶  ↑o  𝐴 )  ∈  ( 𝐶  ↑o  𝑥 )  ↔  ( 𝐶  ↑o  𝐴 )  ∈  ∪  𝑦  ∈  𝑥 ( 𝐶  ↑o  𝑦 ) ) ) | 
						
							| 92 | 82 91 | sylibrd | ⊢ ( ( ( Lim  𝑥  ∧  𝐴  ∈  𝑥 )  ∧  𝐶  ∈  ( On  ∖  2o ) )  →  ( ∀ 𝑦  ∈  𝑥 ( 𝐴  ∈  𝑦  →  ( 𝐶  ↑o  𝐴 )  ∈  ( 𝐶  ↑o  𝑦 ) )  →  ( 𝐶  ↑o  𝐴 )  ∈  ( 𝐶  ↑o  𝑥 ) ) ) | 
						
							| 93 | 92 | ex | ⊢ ( ( Lim  𝑥  ∧  𝐴  ∈  𝑥 )  →  ( 𝐶  ∈  ( On  ∖  2o )  →  ( ∀ 𝑦  ∈  𝑥 ( 𝐴  ∈  𝑦  →  ( 𝐶  ↑o  𝐴 )  ∈  ( 𝐶  ↑o  𝑦 ) )  →  ( 𝐶  ↑o  𝐴 )  ∈  ( 𝐶  ↑o  𝑥 ) ) ) ) | 
						
							| 94 | 93 | a2d | ⊢ ( ( Lim  𝑥  ∧  𝐴  ∈  𝑥 )  →  ( ( 𝐶  ∈  ( On  ∖  2o )  →  ∀ 𝑦  ∈  𝑥 ( 𝐴  ∈  𝑦  →  ( 𝐶  ↑o  𝐴 )  ∈  ( 𝐶  ↑o  𝑦 ) ) )  →  ( 𝐶  ∈  ( On  ∖  2o )  →  ( 𝐶  ↑o  𝐴 )  ∈  ( 𝐶  ↑o  𝑥 ) ) ) ) | 
						
							| 95 | 64 94 | biimtrid | ⊢ ( ( Lim  𝑥  ∧  𝐴  ∈  𝑥 )  →  ( ∀ 𝑦  ∈  𝑥 ( 𝐴  ∈  𝑦  →  ( 𝐶  ∈  ( On  ∖  2o )  →  ( 𝐶  ↑o  𝐴 )  ∈  ( 𝐶  ↑o  𝑦 ) ) )  →  ( 𝐶  ∈  ( On  ∖  2o )  →  ( 𝐶  ↑o  𝐴 )  ∈  ( 𝐶  ↑o  𝑥 ) ) ) ) | 
						
							| 96 | 3 6 9 12 34 60 95 | tfindsg2 | ⊢ ( ( 𝐵  ∈  On  ∧  𝐴  ∈  𝐵 )  →  ( 𝐶  ∈  ( On  ∖  2o )  →  ( 𝐶  ↑o  𝐴 )  ∈  ( 𝐶  ↑o  𝐵 ) ) ) | 
						
							| 97 | 96 | impancom | ⊢ ( ( 𝐵  ∈  On  ∧  𝐶  ∈  ( On  ∖  2o ) )  →  ( 𝐴  ∈  𝐵  →  ( 𝐶  ↑o  𝐴 )  ∈  ( 𝐶  ↑o  𝐵 ) ) ) |