| Step | Hyp | Ref | Expression | 
						
							| 1 |  | dstfrv.1 | ⊢ ( 𝜑  →  𝑃  ∈  Prob ) | 
						
							| 2 |  | dstfrv.2 | ⊢ ( 𝜑  →  𝑋  ∈  ( rRndVar ‘ 𝑃 ) ) | 
						
							| 3 |  | 1red | ⊢ ( ( 𝜑  ∧  𝑥  ∈  ∪  dom  𝑃 )  →  1  ∈  ℝ ) | 
						
							| 4 | 1 2 | rrvvf | ⊢ ( 𝜑  →  𝑋 : ∪  dom  𝑃 ⟶ ℝ ) | 
						
							| 5 | 4 | ffvelcdmda | ⊢ ( ( 𝜑  ∧  𝑥  ∈  ∪  dom  𝑃 )  →  ( 𝑋 ‘ 𝑥 )  ∈  ℝ ) | 
						
							| 6 | 3 5 | ifcld | ⊢ ( ( 𝜑  ∧  𝑥  ∈  ∪  dom  𝑃 )  →  if ( ( 𝑋 ‘ 𝑥 )  <  1 ,  1 ,  ( 𝑋 ‘ 𝑥 ) )  ∈  ℝ ) | 
						
							| 7 |  | breq2 | ⊢ ( 1  =  if ( ( 𝑋 ‘ 𝑥 )  <  1 ,  1 ,  ( 𝑋 ‘ 𝑥 ) )  →  ( 1  ≤  1  ↔  1  ≤  if ( ( 𝑋 ‘ 𝑥 )  <  1 ,  1 ,  ( 𝑋 ‘ 𝑥 ) ) ) ) | 
						
							| 8 |  | breq2 | ⊢ ( ( 𝑋 ‘ 𝑥 )  =  if ( ( 𝑋 ‘ 𝑥 )  <  1 ,  1 ,  ( 𝑋 ‘ 𝑥 ) )  →  ( 1  ≤  ( 𝑋 ‘ 𝑥 )  ↔  1  ≤  if ( ( 𝑋 ‘ 𝑥 )  <  1 ,  1 ,  ( 𝑋 ‘ 𝑥 ) ) ) ) | 
						
							| 9 |  | 1le1 | ⊢ 1  ≤  1 | 
						
							| 10 | 9 | a1i | ⊢ ( ( ( 𝜑  ∧  𝑥  ∈  ∪  dom  𝑃 )  ∧  ( 𝑋 ‘ 𝑥 )  <  1 )  →  1  ≤  1 ) | 
						
							| 11 | 3 5 | lenltd | ⊢ ( ( 𝜑  ∧  𝑥  ∈  ∪  dom  𝑃 )  →  ( 1  ≤  ( 𝑋 ‘ 𝑥 )  ↔  ¬  ( 𝑋 ‘ 𝑥 )  <  1 ) ) | 
						
							| 12 | 11 | biimpar | ⊢ ( ( ( 𝜑  ∧  𝑥  ∈  ∪  dom  𝑃 )  ∧  ¬  ( 𝑋 ‘ 𝑥 )  <  1 )  →  1  ≤  ( 𝑋 ‘ 𝑥 ) ) | 
						
							| 13 | 7 8 10 12 | ifbothda | ⊢ ( ( 𝜑  ∧  𝑥  ∈  ∪  dom  𝑃 )  →  1  ≤  if ( ( 𝑋 ‘ 𝑥 )  <  1 ,  1 ,  ( 𝑋 ‘ 𝑥 ) ) ) | 
						
							| 14 |  | flge1nn | ⊢ ( ( if ( ( 𝑋 ‘ 𝑥 )  <  1 ,  1 ,  ( 𝑋 ‘ 𝑥 ) )  ∈  ℝ  ∧  1  ≤  if ( ( 𝑋 ‘ 𝑥 )  <  1 ,  1 ,  ( 𝑋 ‘ 𝑥 ) ) )  →  ( ⌊ ‘ if ( ( 𝑋 ‘ 𝑥 )  <  1 ,  1 ,  ( 𝑋 ‘ 𝑥 ) ) )  ∈  ℕ ) | 
						
							| 15 | 6 13 14 | syl2anc | ⊢ ( ( 𝜑  ∧  𝑥  ∈  ∪  dom  𝑃 )  →  ( ⌊ ‘ if ( ( 𝑋 ‘ 𝑥 )  <  1 ,  1 ,  ( 𝑋 ‘ 𝑥 ) ) )  ∈  ℕ ) | 
						
							| 16 | 15 | peano2nnd | ⊢ ( ( 𝜑  ∧  𝑥  ∈  ∪  dom  𝑃 )  →  ( ( ⌊ ‘ if ( ( 𝑋 ‘ 𝑥 )  <  1 ,  1 ,  ( 𝑋 ‘ 𝑥 ) ) )  +  1 )  ∈  ℕ ) | 
						
							| 17 | 1 | adantr | ⊢ ( ( 𝜑  ∧  𝑥  ∈  ∪  dom  𝑃 )  →  𝑃  ∈  Prob ) | 
						
							| 18 | 2 | adantr | ⊢ ( ( 𝜑  ∧  𝑥  ∈  ∪  dom  𝑃 )  →  𝑋  ∈  ( rRndVar ‘ 𝑃 ) ) | 
						
							| 19 | 16 | nnred | ⊢ ( ( 𝜑  ∧  𝑥  ∈  ∪  dom  𝑃 )  →  ( ( ⌊ ‘ if ( ( 𝑋 ‘ 𝑥 )  <  1 ,  1 ,  ( 𝑋 ‘ 𝑥 ) ) )  +  1 )  ∈  ℝ ) | 
						
							| 20 |  | simpr | ⊢ ( ( 𝜑  ∧  𝑥  ∈  ∪  dom  𝑃 )  →  𝑥  ∈  ∪  dom  𝑃 ) | 
						
							| 21 |  | breq2 | ⊢ ( 1  =  if ( ( 𝑋 ‘ 𝑥 )  <  1 ,  1 ,  ( 𝑋 ‘ 𝑥 ) )  →  ( ( 𝑋 ‘ 𝑥 )  ≤  1  ↔  ( 𝑋 ‘ 𝑥 )  ≤  if ( ( 𝑋 ‘ 𝑥 )  <  1 ,  1 ,  ( 𝑋 ‘ 𝑥 ) ) ) ) | 
						
							| 22 |  | breq2 | ⊢ ( ( 𝑋 ‘ 𝑥 )  =  if ( ( 𝑋 ‘ 𝑥 )  <  1 ,  1 ,  ( 𝑋 ‘ 𝑥 ) )  →  ( ( 𝑋 ‘ 𝑥 )  ≤  ( 𝑋 ‘ 𝑥 )  ↔  ( 𝑋 ‘ 𝑥 )  ≤  if ( ( 𝑋 ‘ 𝑥 )  <  1 ,  1 ,  ( 𝑋 ‘ 𝑥 ) ) ) ) | 
						
							| 23 | 5 | adantr | ⊢ ( ( ( 𝜑  ∧  𝑥  ∈  ∪  dom  𝑃 )  ∧  ( 𝑋 ‘ 𝑥 )  <  1 )  →  ( 𝑋 ‘ 𝑥 )  ∈  ℝ ) | 
						
							| 24 |  | 1red | ⊢ ( ( ( 𝜑  ∧  𝑥  ∈  ∪  dom  𝑃 )  ∧  ( 𝑋 ‘ 𝑥 )  <  1 )  →  1  ∈  ℝ ) | 
						
							| 25 |  | simpr | ⊢ ( ( ( 𝜑  ∧  𝑥  ∈  ∪  dom  𝑃 )  ∧  ( 𝑋 ‘ 𝑥 )  <  1 )  →  ( 𝑋 ‘ 𝑥 )  <  1 ) | 
						
							| 26 | 23 24 25 | ltled | ⊢ ( ( ( 𝜑  ∧  𝑥  ∈  ∪  dom  𝑃 )  ∧  ( 𝑋 ‘ 𝑥 )  <  1 )  →  ( 𝑋 ‘ 𝑥 )  ≤  1 ) | 
						
							| 27 | 5 | leidd | ⊢ ( ( 𝜑  ∧  𝑥  ∈  ∪  dom  𝑃 )  →  ( 𝑋 ‘ 𝑥 )  ≤  ( 𝑋 ‘ 𝑥 ) ) | 
						
							| 28 | 27 | adantr | ⊢ ( ( ( 𝜑  ∧  𝑥  ∈  ∪  dom  𝑃 )  ∧  ¬  ( 𝑋 ‘ 𝑥 )  <  1 )  →  ( 𝑋 ‘ 𝑥 )  ≤  ( 𝑋 ‘ 𝑥 ) ) | 
						
							| 29 | 21 22 26 28 | ifbothda | ⊢ ( ( 𝜑  ∧  𝑥  ∈  ∪  dom  𝑃 )  →  ( 𝑋 ‘ 𝑥 )  ≤  if ( ( 𝑋 ‘ 𝑥 )  <  1 ,  1 ,  ( 𝑋 ‘ 𝑥 ) ) ) | 
						
							| 30 |  | fllep1 | ⊢ ( if ( ( 𝑋 ‘ 𝑥 )  <  1 ,  1 ,  ( 𝑋 ‘ 𝑥 ) )  ∈  ℝ  →  if ( ( 𝑋 ‘ 𝑥 )  <  1 ,  1 ,  ( 𝑋 ‘ 𝑥 ) )  ≤  ( ( ⌊ ‘ if ( ( 𝑋 ‘ 𝑥 )  <  1 ,  1 ,  ( 𝑋 ‘ 𝑥 ) ) )  +  1 ) ) | 
						
							| 31 | 6 30 | syl | ⊢ ( ( 𝜑  ∧  𝑥  ∈  ∪  dom  𝑃 )  →  if ( ( 𝑋 ‘ 𝑥 )  <  1 ,  1 ,  ( 𝑋 ‘ 𝑥 ) )  ≤  ( ( ⌊ ‘ if ( ( 𝑋 ‘ 𝑥 )  <  1 ,  1 ,  ( 𝑋 ‘ 𝑥 ) ) )  +  1 ) ) | 
						
							| 32 | 5 6 19 29 31 | letrd | ⊢ ( ( 𝜑  ∧  𝑥  ∈  ∪  dom  𝑃 )  →  ( 𝑋 ‘ 𝑥 )  ≤  ( ( ⌊ ‘ if ( ( 𝑋 ‘ 𝑥 )  <  1 ,  1 ,  ( 𝑋 ‘ 𝑥 ) ) )  +  1 ) ) | 
						
							| 33 | 17 18 19 20 32 | dstfrvel | ⊢ ( ( 𝜑  ∧  𝑥  ∈  ∪  dom  𝑃 )  →  𝑥  ∈  ( 𝑋 ∘RV/𝑐  ≤  ( ( ⌊ ‘ if ( ( 𝑋 ‘ 𝑥 )  <  1 ,  1 ,  ( 𝑋 ‘ 𝑥 ) ) )  +  1 ) ) ) | 
						
							| 34 |  | oveq2 | ⊢ ( 𝑛  =  ( ( ⌊ ‘ if ( ( 𝑋 ‘ 𝑥 )  <  1 ,  1 ,  ( 𝑋 ‘ 𝑥 ) ) )  +  1 )  →  ( 𝑋 ∘RV/𝑐  ≤  𝑛 )  =  ( 𝑋 ∘RV/𝑐  ≤  ( ( ⌊ ‘ if ( ( 𝑋 ‘ 𝑥 )  <  1 ,  1 ,  ( 𝑋 ‘ 𝑥 ) ) )  +  1 ) ) ) | 
						
							| 35 | 34 | eleq2d | ⊢ ( 𝑛  =  ( ( ⌊ ‘ if ( ( 𝑋 ‘ 𝑥 )  <  1 ,  1 ,  ( 𝑋 ‘ 𝑥 ) ) )  +  1 )  →  ( 𝑥  ∈  ( 𝑋 ∘RV/𝑐  ≤  𝑛 )  ↔  𝑥  ∈  ( 𝑋 ∘RV/𝑐  ≤  ( ( ⌊ ‘ if ( ( 𝑋 ‘ 𝑥 )  <  1 ,  1 ,  ( 𝑋 ‘ 𝑥 ) ) )  +  1 ) ) ) ) | 
						
							| 36 | 35 | rspcev | ⊢ ( ( ( ( ⌊ ‘ if ( ( 𝑋 ‘ 𝑥 )  <  1 ,  1 ,  ( 𝑋 ‘ 𝑥 ) ) )  +  1 )  ∈  ℕ  ∧  𝑥  ∈  ( 𝑋 ∘RV/𝑐  ≤  ( ( ⌊ ‘ if ( ( 𝑋 ‘ 𝑥 )  <  1 ,  1 ,  ( 𝑋 ‘ 𝑥 ) ) )  +  1 ) ) )  →  ∃ 𝑛  ∈  ℕ 𝑥  ∈  ( 𝑋 ∘RV/𝑐  ≤  𝑛 ) ) | 
						
							| 37 | 16 33 36 | syl2anc | ⊢ ( ( 𝜑  ∧  𝑥  ∈  ∪  dom  𝑃 )  →  ∃ 𝑛  ∈  ℕ 𝑥  ∈  ( 𝑋 ∘RV/𝑐  ≤  𝑛 ) ) | 
						
							| 38 | 37 | ex | ⊢ ( 𝜑  →  ( 𝑥  ∈  ∪  dom  𝑃  →  ∃ 𝑛  ∈  ℕ 𝑥  ∈  ( 𝑋 ∘RV/𝑐  ≤  𝑛 ) ) ) | 
						
							| 39 | 1 | adantr | ⊢ ( ( 𝜑  ∧  𝑛  ∈  ℕ )  →  𝑃  ∈  Prob ) | 
						
							| 40 | 2 | adantr | ⊢ ( ( 𝜑  ∧  𝑛  ∈  ℕ )  →  𝑋  ∈  ( rRndVar ‘ 𝑃 ) ) | 
						
							| 41 |  | simpr | ⊢ ( ( 𝜑  ∧  𝑛  ∈  ℕ )  →  𝑛  ∈  ℕ ) | 
						
							| 42 | 41 | nnred | ⊢ ( ( 𝜑  ∧  𝑛  ∈  ℕ )  →  𝑛  ∈  ℝ ) | 
						
							| 43 | 39 40 42 | orvclteel | ⊢ ( ( 𝜑  ∧  𝑛  ∈  ℕ )  →  ( 𝑋 ∘RV/𝑐  ≤  𝑛 )  ∈  dom  𝑃 ) | 
						
							| 44 |  | elunii | ⊢ ( ( 𝑥  ∈  ( 𝑋 ∘RV/𝑐  ≤  𝑛 )  ∧  ( 𝑋 ∘RV/𝑐  ≤  𝑛 )  ∈  dom  𝑃 )  →  𝑥  ∈  ∪  dom  𝑃 ) | 
						
							| 45 | 44 | expcom | ⊢ ( ( 𝑋 ∘RV/𝑐  ≤  𝑛 )  ∈  dom  𝑃  →  ( 𝑥  ∈  ( 𝑋 ∘RV/𝑐  ≤  𝑛 )  →  𝑥  ∈  ∪  dom  𝑃 ) ) | 
						
							| 46 | 43 45 | syl | ⊢ ( ( 𝜑  ∧  𝑛  ∈  ℕ )  →  ( 𝑥  ∈  ( 𝑋 ∘RV/𝑐  ≤  𝑛 )  →  𝑥  ∈  ∪  dom  𝑃 ) ) | 
						
							| 47 | 46 | rexlimdva | ⊢ ( 𝜑  →  ( ∃ 𝑛  ∈  ℕ 𝑥  ∈  ( 𝑋 ∘RV/𝑐  ≤  𝑛 )  →  𝑥  ∈  ∪  dom  𝑃 ) ) | 
						
							| 48 | 38 47 | impbid | ⊢ ( 𝜑  →  ( 𝑥  ∈  ∪  dom  𝑃  ↔  ∃ 𝑛  ∈  ℕ 𝑥  ∈  ( 𝑋 ∘RV/𝑐  ≤  𝑛 ) ) ) | 
						
							| 49 |  | eliun | ⊢ ( 𝑥  ∈  ∪  𝑛  ∈  ℕ ( 𝑋 ∘RV/𝑐  ≤  𝑛 )  ↔  ∃ 𝑛  ∈  ℕ 𝑥  ∈  ( 𝑋 ∘RV/𝑐  ≤  𝑛 ) ) | 
						
							| 50 | 48 49 | bitr4di | ⊢ ( 𝜑  →  ( 𝑥  ∈  ∪  dom  𝑃  ↔  𝑥  ∈  ∪  𝑛  ∈  ℕ ( 𝑋 ∘RV/𝑐  ≤  𝑛 ) ) ) | 
						
							| 51 | 50 | eqrdv | ⊢ ( 𝜑  →  ∪  dom  𝑃  =  ∪  𝑛  ∈  ℕ ( 𝑋 ∘RV/𝑐  ≤  𝑛 ) ) | 
						
							| 52 |  | ovex | ⊢ ( 𝑋 ∘RV/𝑐  ≤  𝑛 )  ∈  V | 
						
							| 53 | 52 | dfiun3 | ⊢ ∪  𝑛  ∈  ℕ ( 𝑋 ∘RV/𝑐  ≤  𝑛 )  =  ∪  ran  ( 𝑛  ∈  ℕ  ↦  ( 𝑋 ∘RV/𝑐  ≤  𝑛 ) ) | 
						
							| 54 | 51 53 | eqtr2di | ⊢ ( 𝜑  →  ∪  ran  ( 𝑛  ∈  ℕ  ↦  ( 𝑋 ∘RV/𝑐  ≤  𝑛 ) )  =  ∪  dom  𝑃 ) |