| Step | 
						Hyp | 
						Ref | 
						Expression | 
					
						
							| 1 | 
							
								
							 | 
							ballotth.m | 
							⊢ 𝑀  ∈  ℕ  | 
						
						
							| 2 | 
							
								
							 | 
							ballotth.n | 
							⊢ 𝑁  ∈  ℕ  | 
						
						
							| 3 | 
							
								
							 | 
							ballotth.o | 
							⊢ 𝑂  =  { 𝑐  ∈  𝒫  ( 1 ... ( 𝑀  +  𝑁 ) )  ∣  ( ♯ ‘ 𝑐 )  =  𝑀 }  | 
						
						
							| 4 | 
							
								
							 | 
							ballotth.p | 
							⊢ 𝑃  =  ( 𝑥  ∈  𝒫  𝑂  ↦  ( ( ♯ ‘ 𝑥 )  /  ( ♯ ‘ 𝑂 ) ) )  | 
						
						
							| 5 | 
							
								
							 | 
							ballotth.f | 
							⊢ 𝐹  =  ( 𝑐  ∈  𝑂  ↦  ( 𝑖  ∈  ℤ  ↦  ( ( ♯ ‘ ( ( 1 ... 𝑖 )  ∩  𝑐 ) )  −  ( ♯ ‘ ( ( 1 ... 𝑖 )  ∖  𝑐 ) ) ) ) )  | 
						
						
							| 6 | 
							
								
							 | 
							ballotth.e | 
							⊢ 𝐸  =  { 𝑐  ∈  𝑂  ∣  ∀ 𝑖  ∈  ( 1 ... ( 𝑀  +  𝑁 ) ) 0  <  ( ( 𝐹 ‘ 𝑐 ) ‘ 𝑖 ) }  | 
						
						
							| 7 | 
							
								
							 | 
							fveq2 | 
							⊢ ( 𝑑  =  𝐶  →  ( 𝐹 ‘ 𝑑 )  =  ( 𝐹 ‘ 𝐶 ) )  | 
						
						
							| 8 | 
							
								7
							 | 
							fveq1d | 
							⊢ ( 𝑑  =  𝐶  →  ( ( 𝐹 ‘ 𝑑 ) ‘ 𝑖 )  =  ( ( 𝐹 ‘ 𝐶 ) ‘ 𝑖 ) )  | 
						
						
							| 9 | 
							
								8
							 | 
							breq2d | 
							⊢ ( 𝑑  =  𝐶  →  ( 0  <  ( ( 𝐹 ‘ 𝑑 ) ‘ 𝑖 )  ↔  0  <  ( ( 𝐹 ‘ 𝐶 ) ‘ 𝑖 ) ) )  | 
						
						
							| 10 | 
							
								9
							 | 
							ralbidv | 
							⊢ ( 𝑑  =  𝐶  →  ( ∀ 𝑖  ∈  ( 1 ... ( 𝑀  +  𝑁 ) ) 0  <  ( ( 𝐹 ‘ 𝑑 ) ‘ 𝑖 )  ↔  ∀ 𝑖  ∈  ( 1 ... ( 𝑀  +  𝑁 ) ) 0  <  ( ( 𝐹 ‘ 𝐶 ) ‘ 𝑖 ) ) )  | 
						
						
							| 11 | 
							
								
							 | 
							fveq2 | 
							⊢ ( 𝑐  =  𝑑  →  ( 𝐹 ‘ 𝑐 )  =  ( 𝐹 ‘ 𝑑 ) )  | 
						
						
							| 12 | 
							
								11
							 | 
							fveq1d | 
							⊢ ( 𝑐  =  𝑑  →  ( ( 𝐹 ‘ 𝑐 ) ‘ 𝑖 )  =  ( ( 𝐹 ‘ 𝑑 ) ‘ 𝑖 ) )  | 
						
						
							| 13 | 
							
								12
							 | 
							breq2d | 
							⊢ ( 𝑐  =  𝑑  →  ( 0  <  ( ( 𝐹 ‘ 𝑐 ) ‘ 𝑖 )  ↔  0  <  ( ( 𝐹 ‘ 𝑑 ) ‘ 𝑖 ) ) )  | 
						
						
							| 14 | 
							
								13
							 | 
							ralbidv | 
							⊢ ( 𝑐  =  𝑑  →  ( ∀ 𝑖  ∈  ( 1 ... ( 𝑀  +  𝑁 ) ) 0  <  ( ( 𝐹 ‘ 𝑐 ) ‘ 𝑖 )  ↔  ∀ 𝑖  ∈  ( 1 ... ( 𝑀  +  𝑁 ) ) 0  <  ( ( 𝐹 ‘ 𝑑 ) ‘ 𝑖 ) ) )  | 
						
						
							| 15 | 
							
								14
							 | 
							cbvrabv | 
							⊢ { 𝑐  ∈  𝑂  ∣  ∀ 𝑖  ∈  ( 1 ... ( 𝑀  +  𝑁 ) ) 0  <  ( ( 𝐹 ‘ 𝑐 ) ‘ 𝑖 ) }  =  { 𝑑  ∈  𝑂  ∣  ∀ 𝑖  ∈  ( 1 ... ( 𝑀  +  𝑁 ) ) 0  <  ( ( 𝐹 ‘ 𝑑 ) ‘ 𝑖 ) }  | 
						
						
							| 16 | 
							
								6 15
							 | 
							eqtri | 
							⊢ 𝐸  =  { 𝑑  ∈  𝑂  ∣  ∀ 𝑖  ∈  ( 1 ... ( 𝑀  +  𝑁 ) ) 0  <  ( ( 𝐹 ‘ 𝑑 ) ‘ 𝑖 ) }  | 
						
						
							| 17 | 
							
								10 16
							 | 
							elrab2 | 
							⊢ ( 𝐶  ∈  𝐸  ↔  ( 𝐶  ∈  𝑂  ∧  ∀ 𝑖  ∈  ( 1 ... ( 𝑀  +  𝑁 ) ) 0  <  ( ( 𝐹 ‘ 𝐶 ) ‘ 𝑖 ) ) )  |