| Step | Hyp | Ref | Expression | 
						
							| 1 |  | eulerpart.p | ⊢ 𝑃  =  { 𝑓  ∈  ( ℕ0  ↑m  ℕ )  ∣  ( ( ◡ 𝑓  “  ℕ )  ∈  Fin  ∧  Σ 𝑘  ∈  ℕ ( ( 𝑓 ‘ 𝑘 )  ·  𝑘 )  =  𝑁 ) } | 
						
							| 2 |  | eulerpart.o | ⊢ 𝑂  =  { 𝑔  ∈  𝑃  ∣  ∀ 𝑛  ∈  ( ◡ 𝑔  “  ℕ ) ¬  2  ∥  𝑛 } | 
						
							| 3 |  | eulerpart.d | ⊢ 𝐷  =  { 𝑔  ∈  𝑃  ∣  ∀ 𝑛  ∈  ℕ ( 𝑔 ‘ 𝑛 )  ≤  1 } | 
						
							| 4 |  | fveq1 | ⊢ ( 𝑔  =  𝐴  →  ( 𝑔 ‘ 𝑛 )  =  ( 𝐴 ‘ 𝑛 ) ) | 
						
							| 5 | 4 | breq1d | ⊢ ( 𝑔  =  𝐴  →  ( ( 𝑔 ‘ 𝑛 )  ≤  1  ↔  ( 𝐴 ‘ 𝑛 )  ≤  1 ) ) | 
						
							| 6 | 5 | ralbidv | ⊢ ( 𝑔  =  𝐴  →  ( ∀ 𝑛  ∈  ℕ ( 𝑔 ‘ 𝑛 )  ≤  1  ↔  ∀ 𝑛  ∈  ℕ ( 𝐴 ‘ 𝑛 )  ≤  1 ) ) | 
						
							| 7 | 6 3 | elrab2 | ⊢ ( 𝐴  ∈  𝐷  ↔  ( 𝐴  ∈  𝑃  ∧  ∀ 𝑛  ∈  ℕ ( 𝐴 ‘ 𝑛 )  ≤  1 ) ) | 
						
							| 8 |  | 2z | ⊢ 2  ∈  ℤ | 
						
							| 9 |  | fzoval | ⊢ ( 2  ∈  ℤ  →  ( 0 ..^ 2 )  =  ( 0 ... ( 2  −  1 ) ) ) | 
						
							| 10 | 8 9 | ax-mp | ⊢ ( 0 ..^ 2 )  =  ( 0 ... ( 2  −  1 ) ) | 
						
							| 11 |  | fzo0to2pr | ⊢ ( 0 ..^ 2 )  =  { 0 ,  1 } | 
						
							| 12 |  | 2m1e1 | ⊢ ( 2  −  1 )  =  1 | 
						
							| 13 | 12 | oveq2i | ⊢ ( 0 ... ( 2  −  1 ) )  =  ( 0 ... 1 ) | 
						
							| 14 | 10 11 13 | 3eqtr3i | ⊢ { 0 ,  1 }  =  ( 0 ... 1 ) | 
						
							| 15 | 14 | eleq2i | ⊢ ( ( 𝐴 ‘ 𝑛 )  ∈  { 0 ,  1 }  ↔  ( 𝐴 ‘ 𝑛 )  ∈  ( 0 ... 1 ) ) | 
						
							| 16 | 1 | eulerpartleme | ⊢ ( 𝐴  ∈  𝑃  ↔  ( 𝐴 : ℕ ⟶ ℕ0  ∧  ( ◡ 𝐴  “  ℕ )  ∈  Fin  ∧  Σ 𝑘  ∈  ℕ ( ( 𝐴 ‘ 𝑘 )  ·  𝑘 )  =  𝑁 ) ) | 
						
							| 17 | 16 | simp1bi | ⊢ ( 𝐴  ∈  𝑃  →  𝐴 : ℕ ⟶ ℕ0 ) | 
						
							| 18 | 17 | ffvelcdmda | ⊢ ( ( 𝐴  ∈  𝑃  ∧  𝑛  ∈  ℕ )  →  ( 𝐴 ‘ 𝑛 )  ∈  ℕ0 ) | 
						
							| 19 |  | 1nn0 | ⊢ 1  ∈  ℕ0 | 
						
							| 20 |  | elfz2nn0 | ⊢ ( ( 𝐴 ‘ 𝑛 )  ∈  ( 0 ... 1 )  ↔  ( ( 𝐴 ‘ 𝑛 )  ∈  ℕ0  ∧  1  ∈  ℕ0  ∧  ( 𝐴 ‘ 𝑛 )  ≤  1 ) ) | 
						
							| 21 |  | df-3an | ⊢ ( ( ( 𝐴 ‘ 𝑛 )  ∈  ℕ0  ∧  1  ∈  ℕ0  ∧  ( 𝐴 ‘ 𝑛 )  ≤  1 )  ↔  ( ( ( 𝐴 ‘ 𝑛 )  ∈  ℕ0  ∧  1  ∈  ℕ0 )  ∧  ( 𝐴 ‘ 𝑛 )  ≤  1 ) ) | 
						
							| 22 | 20 21 | bitri | ⊢ ( ( 𝐴 ‘ 𝑛 )  ∈  ( 0 ... 1 )  ↔  ( ( ( 𝐴 ‘ 𝑛 )  ∈  ℕ0  ∧  1  ∈  ℕ0 )  ∧  ( 𝐴 ‘ 𝑛 )  ≤  1 ) ) | 
						
							| 23 | 22 | baib | ⊢ ( ( ( 𝐴 ‘ 𝑛 )  ∈  ℕ0  ∧  1  ∈  ℕ0 )  →  ( ( 𝐴 ‘ 𝑛 )  ∈  ( 0 ... 1 )  ↔  ( 𝐴 ‘ 𝑛 )  ≤  1 ) ) | 
						
							| 24 | 18 19 23 | sylancl | ⊢ ( ( 𝐴  ∈  𝑃  ∧  𝑛  ∈  ℕ )  →  ( ( 𝐴 ‘ 𝑛 )  ∈  ( 0 ... 1 )  ↔  ( 𝐴 ‘ 𝑛 )  ≤  1 ) ) | 
						
							| 25 | 15 24 | bitr2id | ⊢ ( ( 𝐴  ∈  𝑃  ∧  𝑛  ∈  ℕ )  →  ( ( 𝐴 ‘ 𝑛 )  ≤  1  ↔  ( 𝐴 ‘ 𝑛 )  ∈  { 0 ,  1 } ) ) | 
						
							| 26 | 25 | ralbidva | ⊢ ( 𝐴  ∈  𝑃  →  ( ∀ 𝑛  ∈  ℕ ( 𝐴 ‘ 𝑛 )  ≤  1  ↔  ∀ 𝑛  ∈  ℕ ( 𝐴 ‘ 𝑛 )  ∈  { 0 ,  1 } ) ) | 
						
							| 27 | 17 | ffund | ⊢ ( 𝐴  ∈  𝑃  →  Fun  𝐴 ) | 
						
							| 28 |  | fdm | ⊢ ( 𝐴 : ℕ ⟶ ℕ0  →  dom  𝐴  =  ℕ ) | 
						
							| 29 |  | eqimss2 | ⊢ ( dom  𝐴  =  ℕ  →  ℕ  ⊆  dom  𝐴 ) | 
						
							| 30 | 17 28 29 | 3syl | ⊢ ( 𝐴  ∈  𝑃  →  ℕ  ⊆  dom  𝐴 ) | 
						
							| 31 |  | funimass4 | ⊢ ( ( Fun  𝐴  ∧  ℕ  ⊆  dom  𝐴 )  →  ( ( 𝐴  “  ℕ )  ⊆  { 0 ,  1 }  ↔  ∀ 𝑛  ∈  ℕ ( 𝐴 ‘ 𝑛 )  ∈  { 0 ,  1 } ) ) | 
						
							| 32 | 27 30 31 | syl2anc | ⊢ ( 𝐴  ∈  𝑃  →  ( ( 𝐴  “  ℕ )  ⊆  { 0 ,  1 }  ↔  ∀ 𝑛  ∈  ℕ ( 𝐴 ‘ 𝑛 )  ∈  { 0 ,  1 } ) ) | 
						
							| 33 | 26 32 | bitr4d | ⊢ ( 𝐴  ∈  𝑃  →  ( ∀ 𝑛  ∈  ℕ ( 𝐴 ‘ 𝑛 )  ≤  1  ↔  ( 𝐴  “  ℕ )  ⊆  { 0 ,  1 } ) ) | 
						
							| 34 | 33 | pm5.32i | ⊢ ( ( 𝐴  ∈  𝑃  ∧  ∀ 𝑛  ∈  ℕ ( 𝐴 ‘ 𝑛 )  ≤  1 )  ↔  ( 𝐴  ∈  𝑃  ∧  ( 𝐴  “  ℕ )  ⊆  { 0 ,  1 } ) ) | 
						
							| 35 | 7 34 | bitri | ⊢ ( 𝐴  ∈  𝐷  ↔  ( 𝐴  ∈  𝑃  ∧  ( 𝐴  “  ℕ )  ⊆  { 0 ,  1 } ) ) |