| Step | Hyp | Ref | Expression | 
						
							| 1 |  | ruc.1 | ⊢ ( 𝜑  →  𝐹 : ℕ ⟶ ℝ ) | 
						
							| 2 |  | ruc.2 | ⊢ ( 𝜑  →  𝐷  =  ( 𝑥  ∈  ( ℝ  ×  ℝ ) ,  𝑦  ∈  ℝ  ↦  ⦋ ( ( ( 1st  ‘ 𝑥 )  +  ( 2nd  ‘ 𝑥 ) )  /  2 )  /  𝑚 ⦌ if ( 𝑚  <  𝑦 ,  〈 ( 1st  ‘ 𝑥 ) ,  𝑚 〉 ,  〈 ( ( 𝑚  +  ( 2nd  ‘ 𝑥 ) )  /  2 ) ,  ( 2nd  ‘ 𝑥 ) 〉 ) ) ) | 
						
							| 3 |  | ruc.4 | ⊢ 𝐶  =  ( { 〈 0 ,  〈 0 ,  1 〉 〉 }  ∪  𝐹 ) | 
						
							| 4 |  | ruc.5 | ⊢ 𝐺  =  seq 0 ( 𝐷 ,  𝐶 ) | 
						
							| 5 | 1 2 3 4 | ruclem6 | ⊢ ( 𝜑  →  𝐺 : ℕ0 ⟶ ( ℝ  ×  ℝ ) ) | 
						
							| 6 |  | 1stcof | ⊢ ( 𝐺 : ℕ0 ⟶ ( ℝ  ×  ℝ )  →  ( 1st   ∘  𝐺 ) : ℕ0 ⟶ ℝ ) | 
						
							| 7 | 5 6 | syl | ⊢ ( 𝜑  →  ( 1st   ∘  𝐺 ) : ℕ0 ⟶ ℝ ) | 
						
							| 8 | 7 | frnd | ⊢ ( 𝜑  →  ran  ( 1st   ∘  𝐺 )  ⊆  ℝ ) | 
						
							| 9 | 7 | fdmd | ⊢ ( 𝜑  →  dom  ( 1st   ∘  𝐺 )  =  ℕ0 ) | 
						
							| 10 |  | 0nn0 | ⊢ 0  ∈  ℕ0 | 
						
							| 11 |  | ne0i | ⊢ ( 0  ∈  ℕ0  →  ℕ0  ≠  ∅ ) | 
						
							| 12 | 10 11 | mp1i | ⊢ ( 𝜑  →  ℕ0  ≠  ∅ ) | 
						
							| 13 | 9 12 | eqnetrd | ⊢ ( 𝜑  →  dom  ( 1st   ∘  𝐺 )  ≠  ∅ ) | 
						
							| 14 |  | dm0rn0 | ⊢ ( dom  ( 1st   ∘  𝐺 )  =  ∅  ↔  ran  ( 1st   ∘  𝐺 )  =  ∅ ) | 
						
							| 15 | 14 | necon3bii | ⊢ ( dom  ( 1st   ∘  𝐺 )  ≠  ∅  ↔  ran  ( 1st   ∘  𝐺 )  ≠  ∅ ) | 
						
							| 16 | 13 15 | sylib | ⊢ ( 𝜑  →  ran  ( 1st   ∘  𝐺 )  ≠  ∅ ) | 
						
							| 17 |  | fvco3 | ⊢ ( ( 𝐺 : ℕ0 ⟶ ( ℝ  ×  ℝ )  ∧  𝑛  ∈  ℕ0 )  →  ( ( 1st   ∘  𝐺 ) ‘ 𝑛 )  =  ( 1st  ‘ ( 𝐺 ‘ 𝑛 ) ) ) | 
						
							| 18 | 5 17 | sylan | ⊢ ( ( 𝜑  ∧  𝑛  ∈  ℕ0 )  →  ( ( 1st   ∘  𝐺 ) ‘ 𝑛 )  =  ( 1st  ‘ ( 𝐺 ‘ 𝑛 ) ) ) | 
						
							| 19 | 1 | adantr | ⊢ ( ( 𝜑  ∧  𝑛  ∈  ℕ0 )  →  𝐹 : ℕ ⟶ ℝ ) | 
						
							| 20 | 2 | adantr | ⊢ ( ( 𝜑  ∧  𝑛  ∈  ℕ0 )  →  𝐷  =  ( 𝑥  ∈  ( ℝ  ×  ℝ ) ,  𝑦  ∈  ℝ  ↦  ⦋ ( ( ( 1st  ‘ 𝑥 )  +  ( 2nd  ‘ 𝑥 ) )  /  2 )  /  𝑚 ⦌ if ( 𝑚  <  𝑦 ,  〈 ( 1st  ‘ 𝑥 ) ,  𝑚 〉 ,  〈 ( ( 𝑚  +  ( 2nd  ‘ 𝑥 ) )  /  2 ) ,  ( 2nd  ‘ 𝑥 ) 〉 ) ) ) | 
						
							| 21 |  | simpr | ⊢ ( ( 𝜑  ∧  𝑛  ∈  ℕ0 )  →  𝑛  ∈  ℕ0 ) | 
						
							| 22 | 10 | a1i | ⊢ ( ( 𝜑  ∧  𝑛  ∈  ℕ0 )  →  0  ∈  ℕ0 ) | 
						
							| 23 | 19 20 3 4 21 22 | ruclem10 | ⊢ ( ( 𝜑  ∧  𝑛  ∈  ℕ0 )  →  ( 1st  ‘ ( 𝐺 ‘ 𝑛 ) )  <  ( 2nd  ‘ ( 𝐺 ‘ 0 ) ) ) | 
						
							| 24 | 1 2 3 4 | ruclem4 | ⊢ ( 𝜑  →  ( 𝐺 ‘ 0 )  =  〈 0 ,  1 〉 ) | 
						
							| 25 | 24 | fveq2d | ⊢ ( 𝜑  →  ( 2nd  ‘ ( 𝐺 ‘ 0 ) )  =  ( 2nd  ‘ 〈 0 ,  1 〉 ) ) | 
						
							| 26 |  | c0ex | ⊢ 0  ∈  V | 
						
							| 27 |  | 1ex | ⊢ 1  ∈  V | 
						
							| 28 | 26 27 | op2nd | ⊢ ( 2nd  ‘ 〈 0 ,  1 〉 )  =  1 | 
						
							| 29 | 25 28 | eqtrdi | ⊢ ( 𝜑  →  ( 2nd  ‘ ( 𝐺 ‘ 0 ) )  =  1 ) | 
						
							| 30 | 29 | adantr | ⊢ ( ( 𝜑  ∧  𝑛  ∈  ℕ0 )  →  ( 2nd  ‘ ( 𝐺 ‘ 0 ) )  =  1 ) | 
						
							| 31 | 23 30 | breqtrd | ⊢ ( ( 𝜑  ∧  𝑛  ∈  ℕ0 )  →  ( 1st  ‘ ( 𝐺 ‘ 𝑛 ) )  <  1 ) | 
						
							| 32 | 5 | ffvelcdmda | ⊢ ( ( 𝜑  ∧  𝑛  ∈  ℕ0 )  →  ( 𝐺 ‘ 𝑛 )  ∈  ( ℝ  ×  ℝ ) ) | 
						
							| 33 |  | xp1st | ⊢ ( ( 𝐺 ‘ 𝑛 )  ∈  ( ℝ  ×  ℝ )  →  ( 1st  ‘ ( 𝐺 ‘ 𝑛 ) )  ∈  ℝ ) | 
						
							| 34 | 32 33 | syl | ⊢ ( ( 𝜑  ∧  𝑛  ∈  ℕ0 )  →  ( 1st  ‘ ( 𝐺 ‘ 𝑛 ) )  ∈  ℝ ) | 
						
							| 35 |  | 1re | ⊢ 1  ∈  ℝ | 
						
							| 36 |  | ltle | ⊢ ( ( ( 1st  ‘ ( 𝐺 ‘ 𝑛 ) )  ∈  ℝ  ∧  1  ∈  ℝ )  →  ( ( 1st  ‘ ( 𝐺 ‘ 𝑛 ) )  <  1  →  ( 1st  ‘ ( 𝐺 ‘ 𝑛 ) )  ≤  1 ) ) | 
						
							| 37 | 34 35 36 | sylancl | ⊢ ( ( 𝜑  ∧  𝑛  ∈  ℕ0 )  →  ( ( 1st  ‘ ( 𝐺 ‘ 𝑛 ) )  <  1  →  ( 1st  ‘ ( 𝐺 ‘ 𝑛 ) )  ≤  1 ) ) | 
						
							| 38 | 31 37 | mpd | ⊢ ( ( 𝜑  ∧  𝑛  ∈  ℕ0 )  →  ( 1st  ‘ ( 𝐺 ‘ 𝑛 ) )  ≤  1 ) | 
						
							| 39 | 18 38 | eqbrtrd | ⊢ ( ( 𝜑  ∧  𝑛  ∈  ℕ0 )  →  ( ( 1st   ∘  𝐺 ) ‘ 𝑛 )  ≤  1 ) | 
						
							| 40 | 39 | ralrimiva | ⊢ ( 𝜑  →  ∀ 𝑛  ∈  ℕ0 ( ( 1st   ∘  𝐺 ) ‘ 𝑛 )  ≤  1 ) | 
						
							| 41 | 7 | ffnd | ⊢ ( 𝜑  →  ( 1st   ∘  𝐺 )  Fn  ℕ0 ) | 
						
							| 42 |  | breq1 | ⊢ ( 𝑧  =  ( ( 1st   ∘  𝐺 ) ‘ 𝑛 )  →  ( 𝑧  ≤  1  ↔  ( ( 1st   ∘  𝐺 ) ‘ 𝑛 )  ≤  1 ) ) | 
						
							| 43 | 42 | ralrn | ⊢ ( ( 1st   ∘  𝐺 )  Fn  ℕ0  →  ( ∀ 𝑧  ∈  ran  ( 1st   ∘  𝐺 ) 𝑧  ≤  1  ↔  ∀ 𝑛  ∈  ℕ0 ( ( 1st   ∘  𝐺 ) ‘ 𝑛 )  ≤  1 ) ) | 
						
							| 44 | 41 43 | syl | ⊢ ( 𝜑  →  ( ∀ 𝑧  ∈  ran  ( 1st   ∘  𝐺 ) 𝑧  ≤  1  ↔  ∀ 𝑛  ∈  ℕ0 ( ( 1st   ∘  𝐺 ) ‘ 𝑛 )  ≤  1 ) ) | 
						
							| 45 | 40 44 | mpbird | ⊢ ( 𝜑  →  ∀ 𝑧  ∈  ran  ( 1st   ∘  𝐺 ) 𝑧  ≤  1 ) | 
						
							| 46 | 8 16 45 | 3jca | ⊢ ( 𝜑  →  ( ran  ( 1st   ∘  𝐺 )  ⊆  ℝ  ∧  ran  ( 1st   ∘  𝐺 )  ≠  ∅  ∧  ∀ 𝑧  ∈  ran  ( 1st   ∘  𝐺 ) 𝑧  ≤  1 ) ) |