| Step | Hyp | Ref | Expression | 
						
							| 1 |  | upgrres.v | ⊢ 𝑉  =  ( Vtx ‘ 𝐺 ) | 
						
							| 2 |  | upgrres.e | ⊢ 𝐸  =  ( iEdg ‘ 𝐺 ) | 
						
							| 3 |  | upgrres.f | ⊢ 𝐹  =  { 𝑖  ∈  dom  𝐸  ∣  𝑁  ∉  ( 𝐸 ‘ 𝑖 ) } | 
						
							| 4 |  | df-ima | ⊢ ( 𝐸  “  𝐹 )  =  ran  ( 𝐸  ↾  𝐹 ) | 
						
							| 5 |  | fveq2 | ⊢ ( 𝑖  =  𝑗  →  ( 𝐸 ‘ 𝑖 )  =  ( 𝐸 ‘ 𝑗 ) ) | 
						
							| 6 |  | neleq2 | ⊢ ( ( 𝐸 ‘ 𝑖 )  =  ( 𝐸 ‘ 𝑗 )  →  ( 𝑁  ∉  ( 𝐸 ‘ 𝑖 )  ↔  𝑁  ∉  ( 𝐸 ‘ 𝑗 ) ) ) | 
						
							| 7 | 5 6 | syl | ⊢ ( 𝑖  =  𝑗  →  ( 𝑁  ∉  ( 𝐸 ‘ 𝑖 )  ↔  𝑁  ∉  ( 𝐸 ‘ 𝑗 ) ) ) | 
						
							| 8 | 7 3 | elrab2 | ⊢ ( 𝑗  ∈  𝐹  ↔  ( 𝑗  ∈  dom  𝐸  ∧  𝑁  ∉  ( 𝐸 ‘ 𝑗 ) ) ) | 
						
							| 9 | 1 2 | upgrf | ⊢ ( 𝐺  ∈  UPGraph  →  𝐸 : dom  𝐸 ⟶ { 𝑝  ∈  ( 𝒫  𝑉  ∖  { ∅ } )  ∣  ( ♯ ‘ 𝑝 )  ≤  2 } ) | 
						
							| 10 |  | ffvelcdm | ⊢ ( ( 𝐸 : dom  𝐸 ⟶ { 𝑝  ∈  ( 𝒫  𝑉  ∖  { ∅ } )  ∣  ( ♯ ‘ 𝑝 )  ≤  2 }  ∧  𝑗  ∈  dom  𝐸 )  →  ( 𝐸 ‘ 𝑗 )  ∈  { 𝑝  ∈  ( 𝒫  𝑉  ∖  { ∅ } )  ∣  ( ♯ ‘ 𝑝 )  ≤  2 } ) | 
						
							| 11 |  | fveq2 | ⊢ ( 𝑝  =  ( 𝐸 ‘ 𝑗 )  →  ( ♯ ‘ 𝑝 )  =  ( ♯ ‘ ( 𝐸 ‘ 𝑗 ) ) ) | 
						
							| 12 | 11 | breq1d | ⊢ ( 𝑝  =  ( 𝐸 ‘ 𝑗 )  →  ( ( ♯ ‘ 𝑝 )  ≤  2  ↔  ( ♯ ‘ ( 𝐸 ‘ 𝑗 ) )  ≤  2 ) ) | 
						
							| 13 | 12 | elrab | ⊢ ( ( 𝐸 ‘ 𝑗 )  ∈  { 𝑝  ∈  ( 𝒫  𝑉  ∖  { ∅ } )  ∣  ( ♯ ‘ 𝑝 )  ≤  2 }  ↔  ( ( 𝐸 ‘ 𝑗 )  ∈  ( 𝒫  𝑉  ∖  { ∅ } )  ∧  ( ♯ ‘ ( 𝐸 ‘ 𝑗 ) )  ≤  2 ) ) | 
						
							| 14 |  | eldifsn | ⊢ ( ( 𝐸 ‘ 𝑗 )  ∈  ( 𝒫  𝑉  ∖  { ∅ } )  ↔  ( ( 𝐸 ‘ 𝑗 )  ∈  𝒫  𝑉  ∧  ( 𝐸 ‘ 𝑗 )  ≠  ∅ ) ) | 
						
							| 15 |  | simpl | ⊢ ( ( ( 𝐸 ‘ 𝑗 )  ∈  𝒫  𝑉  ∧  𝑁  ∉  ( 𝐸 ‘ 𝑗 ) )  →  ( 𝐸 ‘ 𝑗 )  ∈  𝒫  𝑉 ) | 
						
							| 16 |  | elpwi | ⊢ ( ( 𝐸 ‘ 𝑗 )  ∈  𝒫  𝑉  →  ( 𝐸 ‘ 𝑗 )  ⊆  𝑉 ) | 
						
							| 17 | 16 | adantr | ⊢ ( ( ( 𝐸 ‘ 𝑗 )  ∈  𝒫  𝑉  ∧  𝑁  ∉  ( 𝐸 ‘ 𝑗 ) )  →  ( 𝐸 ‘ 𝑗 )  ⊆  𝑉 ) | 
						
							| 18 |  | simpr | ⊢ ( ( ( 𝐸 ‘ 𝑗 )  ∈  𝒫  𝑉  ∧  𝑁  ∉  ( 𝐸 ‘ 𝑗 ) )  →  𝑁  ∉  ( 𝐸 ‘ 𝑗 ) ) | 
						
							| 19 |  | elpwdifsn | ⊢ ( ( ( 𝐸 ‘ 𝑗 )  ∈  𝒫  𝑉  ∧  ( 𝐸 ‘ 𝑗 )  ⊆  𝑉  ∧  𝑁  ∉  ( 𝐸 ‘ 𝑗 ) )  →  ( 𝐸 ‘ 𝑗 )  ∈  𝒫  ( 𝑉  ∖  { 𝑁 } ) ) | 
						
							| 20 | 15 17 18 19 | syl3anc | ⊢ ( ( ( 𝐸 ‘ 𝑗 )  ∈  𝒫  𝑉  ∧  𝑁  ∉  ( 𝐸 ‘ 𝑗 ) )  →  ( 𝐸 ‘ 𝑗 )  ∈  𝒫  ( 𝑉  ∖  { 𝑁 } ) ) | 
						
							| 21 | 20 | ex | ⊢ ( ( 𝐸 ‘ 𝑗 )  ∈  𝒫  𝑉  →  ( 𝑁  ∉  ( 𝐸 ‘ 𝑗 )  →  ( 𝐸 ‘ 𝑗 )  ∈  𝒫  ( 𝑉  ∖  { 𝑁 } ) ) ) | 
						
							| 22 | 21 | adantr | ⊢ ( ( ( 𝐸 ‘ 𝑗 )  ∈  𝒫  𝑉  ∧  ( 𝐸 ‘ 𝑗 )  ≠  ∅ )  →  ( 𝑁  ∉  ( 𝐸 ‘ 𝑗 )  →  ( 𝐸 ‘ 𝑗 )  ∈  𝒫  ( 𝑉  ∖  { 𝑁 } ) ) ) | 
						
							| 23 | 14 22 | sylbi | ⊢ ( ( 𝐸 ‘ 𝑗 )  ∈  ( 𝒫  𝑉  ∖  { ∅ } )  →  ( 𝑁  ∉  ( 𝐸 ‘ 𝑗 )  →  ( 𝐸 ‘ 𝑗 )  ∈  𝒫  ( 𝑉  ∖  { 𝑁 } ) ) ) | 
						
							| 24 | 23 | adantr | ⊢ ( ( ( 𝐸 ‘ 𝑗 )  ∈  ( 𝒫  𝑉  ∖  { ∅ } )  ∧  ( ♯ ‘ ( 𝐸 ‘ 𝑗 ) )  ≤  2 )  →  ( 𝑁  ∉  ( 𝐸 ‘ 𝑗 )  →  ( 𝐸 ‘ 𝑗 )  ∈  𝒫  ( 𝑉  ∖  { 𝑁 } ) ) ) | 
						
							| 25 | 24 | imp | ⊢ ( ( ( ( 𝐸 ‘ 𝑗 )  ∈  ( 𝒫  𝑉  ∖  { ∅ } )  ∧  ( ♯ ‘ ( 𝐸 ‘ 𝑗 ) )  ≤  2 )  ∧  𝑁  ∉  ( 𝐸 ‘ 𝑗 ) )  →  ( 𝐸 ‘ 𝑗 )  ∈  𝒫  ( 𝑉  ∖  { 𝑁 } ) ) | 
						
							| 26 |  | eldifsni | ⊢ ( ( 𝐸 ‘ 𝑗 )  ∈  ( 𝒫  𝑉  ∖  { ∅ } )  →  ( 𝐸 ‘ 𝑗 )  ≠  ∅ ) | 
						
							| 27 | 26 | adantr | ⊢ ( ( ( 𝐸 ‘ 𝑗 )  ∈  ( 𝒫  𝑉  ∖  { ∅ } )  ∧  ( ♯ ‘ ( 𝐸 ‘ 𝑗 ) )  ≤  2 )  →  ( 𝐸 ‘ 𝑗 )  ≠  ∅ ) | 
						
							| 28 | 27 | adantr | ⊢ ( ( ( ( 𝐸 ‘ 𝑗 )  ∈  ( 𝒫  𝑉  ∖  { ∅ } )  ∧  ( ♯ ‘ ( 𝐸 ‘ 𝑗 ) )  ≤  2 )  ∧  𝑁  ∉  ( 𝐸 ‘ 𝑗 ) )  →  ( 𝐸 ‘ 𝑗 )  ≠  ∅ ) | 
						
							| 29 |  | eldifsn | ⊢ ( ( 𝐸 ‘ 𝑗 )  ∈  ( 𝒫  ( 𝑉  ∖  { 𝑁 } )  ∖  { ∅ } )  ↔  ( ( 𝐸 ‘ 𝑗 )  ∈  𝒫  ( 𝑉  ∖  { 𝑁 } )  ∧  ( 𝐸 ‘ 𝑗 )  ≠  ∅ ) ) | 
						
							| 30 | 25 28 29 | sylanbrc | ⊢ ( ( ( ( 𝐸 ‘ 𝑗 )  ∈  ( 𝒫  𝑉  ∖  { ∅ } )  ∧  ( ♯ ‘ ( 𝐸 ‘ 𝑗 ) )  ≤  2 )  ∧  𝑁  ∉  ( 𝐸 ‘ 𝑗 ) )  →  ( 𝐸 ‘ 𝑗 )  ∈  ( 𝒫  ( 𝑉  ∖  { 𝑁 } )  ∖  { ∅ } ) ) | 
						
							| 31 |  | simpr | ⊢ ( ( ( 𝐸 ‘ 𝑗 )  ∈  ( 𝒫  𝑉  ∖  { ∅ } )  ∧  ( ♯ ‘ ( 𝐸 ‘ 𝑗 ) )  ≤  2 )  →  ( ♯ ‘ ( 𝐸 ‘ 𝑗 ) )  ≤  2 ) | 
						
							| 32 | 31 | adantr | ⊢ ( ( ( ( 𝐸 ‘ 𝑗 )  ∈  ( 𝒫  𝑉  ∖  { ∅ } )  ∧  ( ♯ ‘ ( 𝐸 ‘ 𝑗 ) )  ≤  2 )  ∧  𝑁  ∉  ( 𝐸 ‘ 𝑗 ) )  →  ( ♯ ‘ ( 𝐸 ‘ 𝑗 ) )  ≤  2 ) | 
						
							| 33 | 12 30 32 | elrabd | ⊢ ( ( ( ( 𝐸 ‘ 𝑗 )  ∈  ( 𝒫  𝑉  ∖  { ∅ } )  ∧  ( ♯ ‘ ( 𝐸 ‘ 𝑗 ) )  ≤  2 )  ∧  𝑁  ∉  ( 𝐸 ‘ 𝑗 ) )  →  ( 𝐸 ‘ 𝑗 )  ∈  { 𝑝  ∈  ( 𝒫  ( 𝑉  ∖  { 𝑁 } )  ∖  { ∅ } )  ∣  ( ♯ ‘ 𝑝 )  ≤  2 } ) | 
						
							| 34 | 33 | ex | ⊢ ( ( ( 𝐸 ‘ 𝑗 )  ∈  ( 𝒫  𝑉  ∖  { ∅ } )  ∧  ( ♯ ‘ ( 𝐸 ‘ 𝑗 ) )  ≤  2 )  →  ( 𝑁  ∉  ( 𝐸 ‘ 𝑗 )  →  ( 𝐸 ‘ 𝑗 )  ∈  { 𝑝  ∈  ( 𝒫  ( 𝑉  ∖  { 𝑁 } )  ∖  { ∅ } )  ∣  ( ♯ ‘ 𝑝 )  ≤  2 } ) ) | 
						
							| 35 | 34 | a1d | ⊢ ( ( ( 𝐸 ‘ 𝑗 )  ∈  ( 𝒫  𝑉  ∖  { ∅ } )  ∧  ( ♯ ‘ ( 𝐸 ‘ 𝑗 ) )  ≤  2 )  →  ( 𝑁  ∈  𝑉  →  ( 𝑁  ∉  ( 𝐸 ‘ 𝑗 )  →  ( 𝐸 ‘ 𝑗 )  ∈  { 𝑝  ∈  ( 𝒫  ( 𝑉  ∖  { 𝑁 } )  ∖  { ∅ } )  ∣  ( ♯ ‘ 𝑝 )  ≤  2 } ) ) ) | 
						
							| 36 | 13 35 | sylbi | ⊢ ( ( 𝐸 ‘ 𝑗 )  ∈  { 𝑝  ∈  ( 𝒫  𝑉  ∖  { ∅ } )  ∣  ( ♯ ‘ 𝑝 )  ≤  2 }  →  ( 𝑁  ∈  𝑉  →  ( 𝑁  ∉  ( 𝐸 ‘ 𝑗 )  →  ( 𝐸 ‘ 𝑗 )  ∈  { 𝑝  ∈  ( 𝒫  ( 𝑉  ∖  { 𝑁 } )  ∖  { ∅ } )  ∣  ( ♯ ‘ 𝑝 )  ≤  2 } ) ) ) | 
						
							| 37 | 10 36 | syl | ⊢ ( ( 𝐸 : dom  𝐸 ⟶ { 𝑝  ∈  ( 𝒫  𝑉  ∖  { ∅ } )  ∣  ( ♯ ‘ 𝑝 )  ≤  2 }  ∧  𝑗  ∈  dom  𝐸 )  →  ( 𝑁  ∈  𝑉  →  ( 𝑁  ∉  ( 𝐸 ‘ 𝑗 )  →  ( 𝐸 ‘ 𝑗 )  ∈  { 𝑝  ∈  ( 𝒫  ( 𝑉  ∖  { 𝑁 } )  ∖  { ∅ } )  ∣  ( ♯ ‘ 𝑝 )  ≤  2 } ) ) ) | 
						
							| 38 | 37 | ex | ⊢ ( 𝐸 : dom  𝐸 ⟶ { 𝑝  ∈  ( 𝒫  𝑉  ∖  { ∅ } )  ∣  ( ♯ ‘ 𝑝 )  ≤  2 }  →  ( 𝑗  ∈  dom  𝐸  →  ( 𝑁  ∈  𝑉  →  ( 𝑁  ∉  ( 𝐸 ‘ 𝑗 )  →  ( 𝐸 ‘ 𝑗 )  ∈  { 𝑝  ∈  ( 𝒫  ( 𝑉  ∖  { 𝑁 } )  ∖  { ∅ } )  ∣  ( ♯ ‘ 𝑝 )  ≤  2 } ) ) ) ) | 
						
							| 39 | 38 | com23 | ⊢ ( 𝐸 : dom  𝐸 ⟶ { 𝑝  ∈  ( 𝒫  𝑉  ∖  { ∅ } )  ∣  ( ♯ ‘ 𝑝 )  ≤  2 }  →  ( 𝑁  ∈  𝑉  →  ( 𝑗  ∈  dom  𝐸  →  ( 𝑁  ∉  ( 𝐸 ‘ 𝑗 )  →  ( 𝐸 ‘ 𝑗 )  ∈  { 𝑝  ∈  ( 𝒫  ( 𝑉  ∖  { 𝑁 } )  ∖  { ∅ } )  ∣  ( ♯ ‘ 𝑝 )  ≤  2 } ) ) ) ) | 
						
							| 40 | 9 39 | syl | ⊢ ( 𝐺  ∈  UPGraph  →  ( 𝑁  ∈  𝑉  →  ( 𝑗  ∈  dom  𝐸  →  ( 𝑁  ∉  ( 𝐸 ‘ 𝑗 )  →  ( 𝐸 ‘ 𝑗 )  ∈  { 𝑝  ∈  ( 𝒫  ( 𝑉  ∖  { 𝑁 } )  ∖  { ∅ } )  ∣  ( ♯ ‘ 𝑝 )  ≤  2 } ) ) ) ) | 
						
							| 41 | 40 | imp4b | ⊢ ( ( 𝐺  ∈  UPGraph  ∧  𝑁  ∈  𝑉 )  →  ( ( 𝑗  ∈  dom  𝐸  ∧  𝑁  ∉  ( 𝐸 ‘ 𝑗 ) )  →  ( 𝐸 ‘ 𝑗 )  ∈  { 𝑝  ∈  ( 𝒫  ( 𝑉  ∖  { 𝑁 } )  ∖  { ∅ } )  ∣  ( ♯ ‘ 𝑝 )  ≤  2 } ) ) | 
						
							| 42 | 8 41 | biimtrid | ⊢ ( ( 𝐺  ∈  UPGraph  ∧  𝑁  ∈  𝑉 )  →  ( 𝑗  ∈  𝐹  →  ( 𝐸 ‘ 𝑗 )  ∈  { 𝑝  ∈  ( 𝒫  ( 𝑉  ∖  { 𝑁 } )  ∖  { ∅ } )  ∣  ( ♯ ‘ 𝑝 )  ≤  2 } ) ) | 
						
							| 43 | 42 | ralrimiv | ⊢ ( ( 𝐺  ∈  UPGraph  ∧  𝑁  ∈  𝑉 )  →  ∀ 𝑗  ∈  𝐹 ( 𝐸 ‘ 𝑗 )  ∈  { 𝑝  ∈  ( 𝒫  ( 𝑉  ∖  { 𝑁 } )  ∖  { ∅ } )  ∣  ( ♯ ‘ 𝑝 )  ≤  2 } ) | 
						
							| 44 |  | upgruhgr | ⊢ ( 𝐺  ∈  UPGraph  →  𝐺  ∈  UHGraph ) | 
						
							| 45 | 2 | uhgrfun | ⊢ ( 𝐺  ∈  UHGraph  →  Fun  𝐸 ) | 
						
							| 46 | 44 45 | syl | ⊢ ( 𝐺  ∈  UPGraph  →  Fun  𝐸 ) | 
						
							| 47 | 46 | adantr | ⊢ ( ( 𝐺  ∈  UPGraph  ∧  𝑁  ∈  𝑉 )  →  Fun  𝐸 ) | 
						
							| 48 | 3 | ssrab3 | ⊢ 𝐹  ⊆  dom  𝐸 | 
						
							| 49 |  | funimass4 | ⊢ ( ( Fun  𝐸  ∧  𝐹  ⊆  dom  𝐸 )  →  ( ( 𝐸  “  𝐹 )  ⊆  { 𝑝  ∈  ( 𝒫  ( 𝑉  ∖  { 𝑁 } )  ∖  { ∅ } )  ∣  ( ♯ ‘ 𝑝 )  ≤  2 }  ↔  ∀ 𝑗  ∈  𝐹 ( 𝐸 ‘ 𝑗 )  ∈  { 𝑝  ∈  ( 𝒫  ( 𝑉  ∖  { 𝑁 } )  ∖  { ∅ } )  ∣  ( ♯ ‘ 𝑝 )  ≤  2 } ) ) | 
						
							| 50 | 47 48 49 | sylancl | ⊢ ( ( 𝐺  ∈  UPGraph  ∧  𝑁  ∈  𝑉 )  →  ( ( 𝐸  “  𝐹 )  ⊆  { 𝑝  ∈  ( 𝒫  ( 𝑉  ∖  { 𝑁 } )  ∖  { ∅ } )  ∣  ( ♯ ‘ 𝑝 )  ≤  2 }  ↔  ∀ 𝑗  ∈  𝐹 ( 𝐸 ‘ 𝑗 )  ∈  { 𝑝  ∈  ( 𝒫  ( 𝑉  ∖  { 𝑁 } )  ∖  { ∅ } )  ∣  ( ♯ ‘ 𝑝 )  ≤  2 } ) ) | 
						
							| 51 | 43 50 | mpbird | ⊢ ( ( 𝐺  ∈  UPGraph  ∧  𝑁  ∈  𝑉 )  →  ( 𝐸  “  𝐹 )  ⊆  { 𝑝  ∈  ( 𝒫  ( 𝑉  ∖  { 𝑁 } )  ∖  { ∅ } )  ∣  ( ♯ ‘ 𝑝 )  ≤  2 } ) | 
						
							| 52 | 4 51 | eqsstrrid | ⊢ ( ( 𝐺  ∈  UPGraph  ∧  𝑁  ∈  𝑉 )  →  ran  ( 𝐸  ↾  𝐹 )  ⊆  { 𝑝  ∈  ( 𝒫  ( 𝑉  ∖  { 𝑁 } )  ∖  { ∅ } )  ∣  ( ♯ ‘ 𝑝 )  ≤  2 } ) |