| Step | Hyp | Ref | Expression | 
						
							| 0 |  | ccgr | ⊢ Cgr | 
						
							| 1 |  | vx | ⊢ 𝑥 | 
						
							| 2 |  | vy | ⊢ 𝑦 | 
						
							| 3 |  | vn | ⊢ 𝑛 | 
						
							| 4 |  | cn | ⊢ ℕ | 
						
							| 5 | 1 | cv | ⊢ 𝑥 | 
						
							| 6 |  | cee | ⊢ 𝔼 | 
						
							| 7 | 3 | cv | ⊢ 𝑛 | 
						
							| 8 | 7 6 | cfv | ⊢ ( 𝔼 ‘ 𝑛 ) | 
						
							| 9 | 8 8 | cxp | ⊢ ( ( 𝔼 ‘ 𝑛 )  ×  ( 𝔼 ‘ 𝑛 ) ) | 
						
							| 10 | 5 9 | wcel | ⊢ 𝑥  ∈  ( ( 𝔼 ‘ 𝑛 )  ×  ( 𝔼 ‘ 𝑛 ) ) | 
						
							| 11 | 2 | cv | ⊢ 𝑦 | 
						
							| 12 | 11 9 | wcel | ⊢ 𝑦  ∈  ( ( 𝔼 ‘ 𝑛 )  ×  ( 𝔼 ‘ 𝑛 ) ) | 
						
							| 13 | 10 12 | wa | ⊢ ( 𝑥  ∈  ( ( 𝔼 ‘ 𝑛 )  ×  ( 𝔼 ‘ 𝑛 ) )  ∧  𝑦  ∈  ( ( 𝔼 ‘ 𝑛 )  ×  ( 𝔼 ‘ 𝑛 ) ) ) | 
						
							| 14 |  | vi | ⊢ 𝑖 | 
						
							| 15 |  | c1 | ⊢ 1 | 
						
							| 16 |  | cfz | ⊢ ... | 
						
							| 17 | 15 7 16 | co | ⊢ ( 1 ... 𝑛 ) | 
						
							| 18 |  | c1st | ⊢ 1st | 
						
							| 19 | 5 18 | cfv | ⊢ ( 1st  ‘ 𝑥 ) | 
						
							| 20 | 14 | cv | ⊢ 𝑖 | 
						
							| 21 | 20 19 | cfv | ⊢ ( ( 1st  ‘ 𝑥 ) ‘ 𝑖 ) | 
						
							| 22 |  | cmin | ⊢  − | 
						
							| 23 |  | c2nd | ⊢ 2nd | 
						
							| 24 | 5 23 | cfv | ⊢ ( 2nd  ‘ 𝑥 ) | 
						
							| 25 | 20 24 | cfv | ⊢ ( ( 2nd  ‘ 𝑥 ) ‘ 𝑖 ) | 
						
							| 26 | 21 25 22 | co | ⊢ ( ( ( 1st  ‘ 𝑥 ) ‘ 𝑖 )  −  ( ( 2nd  ‘ 𝑥 ) ‘ 𝑖 ) ) | 
						
							| 27 |  | cexp | ⊢ ↑ | 
						
							| 28 |  | c2 | ⊢ 2 | 
						
							| 29 | 26 28 27 | co | ⊢ ( ( ( ( 1st  ‘ 𝑥 ) ‘ 𝑖 )  −  ( ( 2nd  ‘ 𝑥 ) ‘ 𝑖 ) ) ↑ 2 ) | 
						
							| 30 | 17 29 14 | csu | ⊢ Σ 𝑖  ∈  ( 1 ... 𝑛 ) ( ( ( ( 1st  ‘ 𝑥 ) ‘ 𝑖 )  −  ( ( 2nd  ‘ 𝑥 ) ‘ 𝑖 ) ) ↑ 2 ) | 
						
							| 31 | 11 18 | cfv | ⊢ ( 1st  ‘ 𝑦 ) | 
						
							| 32 | 20 31 | cfv | ⊢ ( ( 1st  ‘ 𝑦 ) ‘ 𝑖 ) | 
						
							| 33 | 11 23 | cfv | ⊢ ( 2nd  ‘ 𝑦 ) | 
						
							| 34 | 20 33 | cfv | ⊢ ( ( 2nd  ‘ 𝑦 ) ‘ 𝑖 ) | 
						
							| 35 | 32 34 22 | co | ⊢ ( ( ( 1st  ‘ 𝑦 ) ‘ 𝑖 )  −  ( ( 2nd  ‘ 𝑦 ) ‘ 𝑖 ) ) | 
						
							| 36 | 35 28 27 | co | ⊢ ( ( ( ( 1st  ‘ 𝑦 ) ‘ 𝑖 )  −  ( ( 2nd  ‘ 𝑦 ) ‘ 𝑖 ) ) ↑ 2 ) | 
						
							| 37 | 17 36 14 | csu | ⊢ Σ 𝑖  ∈  ( 1 ... 𝑛 ) ( ( ( ( 1st  ‘ 𝑦 ) ‘ 𝑖 )  −  ( ( 2nd  ‘ 𝑦 ) ‘ 𝑖 ) ) ↑ 2 ) | 
						
							| 38 | 30 37 | wceq | ⊢ Σ 𝑖  ∈  ( 1 ... 𝑛 ) ( ( ( ( 1st  ‘ 𝑥 ) ‘ 𝑖 )  −  ( ( 2nd  ‘ 𝑥 ) ‘ 𝑖 ) ) ↑ 2 )  =  Σ 𝑖  ∈  ( 1 ... 𝑛 ) ( ( ( ( 1st  ‘ 𝑦 ) ‘ 𝑖 )  −  ( ( 2nd  ‘ 𝑦 ) ‘ 𝑖 ) ) ↑ 2 ) | 
						
							| 39 | 13 38 | wa | ⊢ ( ( 𝑥  ∈  ( ( 𝔼 ‘ 𝑛 )  ×  ( 𝔼 ‘ 𝑛 ) )  ∧  𝑦  ∈  ( ( 𝔼 ‘ 𝑛 )  ×  ( 𝔼 ‘ 𝑛 ) ) )  ∧  Σ 𝑖  ∈  ( 1 ... 𝑛 ) ( ( ( ( 1st  ‘ 𝑥 ) ‘ 𝑖 )  −  ( ( 2nd  ‘ 𝑥 ) ‘ 𝑖 ) ) ↑ 2 )  =  Σ 𝑖  ∈  ( 1 ... 𝑛 ) ( ( ( ( 1st  ‘ 𝑦 ) ‘ 𝑖 )  −  ( ( 2nd  ‘ 𝑦 ) ‘ 𝑖 ) ) ↑ 2 ) ) | 
						
							| 40 | 39 3 4 | wrex | ⊢ ∃ 𝑛  ∈  ℕ ( ( 𝑥  ∈  ( ( 𝔼 ‘ 𝑛 )  ×  ( 𝔼 ‘ 𝑛 ) )  ∧  𝑦  ∈  ( ( 𝔼 ‘ 𝑛 )  ×  ( 𝔼 ‘ 𝑛 ) ) )  ∧  Σ 𝑖  ∈  ( 1 ... 𝑛 ) ( ( ( ( 1st  ‘ 𝑥 ) ‘ 𝑖 )  −  ( ( 2nd  ‘ 𝑥 ) ‘ 𝑖 ) ) ↑ 2 )  =  Σ 𝑖  ∈  ( 1 ... 𝑛 ) ( ( ( ( 1st  ‘ 𝑦 ) ‘ 𝑖 )  −  ( ( 2nd  ‘ 𝑦 ) ‘ 𝑖 ) ) ↑ 2 ) ) | 
						
							| 41 | 40 1 2 | copab | ⊢ { 〈 𝑥 ,  𝑦 〉  ∣  ∃ 𝑛  ∈  ℕ ( ( 𝑥  ∈  ( ( 𝔼 ‘ 𝑛 )  ×  ( 𝔼 ‘ 𝑛 ) )  ∧  𝑦  ∈  ( ( 𝔼 ‘ 𝑛 )  ×  ( 𝔼 ‘ 𝑛 ) ) )  ∧  Σ 𝑖  ∈  ( 1 ... 𝑛 ) ( ( ( ( 1st  ‘ 𝑥 ) ‘ 𝑖 )  −  ( ( 2nd  ‘ 𝑥 ) ‘ 𝑖 ) ) ↑ 2 )  =  Σ 𝑖  ∈  ( 1 ... 𝑛 ) ( ( ( ( 1st  ‘ 𝑦 ) ‘ 𝑖 )  −  ( ( 2nd  ‘ 𝑦 ) ‘ 𝑖 ) ) ↑ 2 ) ) } | 
						
							| 42 | 0 41 | wceq | ⊢ Cgr  =  { 〈 𝑥 ,  𝑦 〉  ∣  ∃ 𝑛  ∈  ℕ ( ( 𝑥  ∈  ( ( 𝔼 ‘ 𝑛 )  ×  ( 𝔼 ‘ 𝑛 ) )  ∧  𝑦  ∈  ( ( 𝔼 ‘ 𝑛 )  ×  ( 𝔼 ‘ 𝑛 ) ) )  ∧  Σ 𝑖  ∈  ( 1 ... 𝑛 ) ( ( ( ( 1st  ‘ 𝑥 ) ‘ 𝑖 )  −  ( ( 2nd  ‘ 𝑥 ) ‘ 𝑖 ) ) ↑ 2 )  =  Σ 𝑖  ∈  ( 1 ... 𝑛 ) ( ( ( ( 1st  ‘ 𝑦 ) ‘ 𝑖 )  −  ( ( 2nd  ‘ 𝑦 ) ‘ 𝑖 ) ) ↑ 2 ) ) } |