Description: An element of the set of simple paths of a fixed length between two vertices as word. (Contributed by Alexander van der Vekens, 1-Mar-2018) (Revised by AV, 12-May-2021) (Revised by AV, 15-Mar-2022)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | wspthnon | ⊢ ( 𝑊 ∈ ( 𝐴 ( 𝑁 WSPathsNOn 𝐺 ) 𝐵 ) ↔ ( 𝑊 ∈ ( 𝐴 ( 𝑁 WWalksNOn 𝐺 ) 𝐵 ) ∧ ∃ 𝑓 𝑓 ( 𝐴 ( SPathsOn ‘ 𝐺 ) 𝐵 ) 𝑊 ) ) | 
| Step | Hyp | Ref | Expression | 
|---|---|---|---|
| 1 | breq2 | ⊢ ( 𝑤 = 𝑊 → ( 𝑓 ( 𝐴 ( SPathsOn ‘ 𝐺 ) 𝐵 ) 𝑤 ↔ 𝑓 ( 𝐴 ( SPathsOn ‘ 𝐺 ) 𝐵 ) 𝑊 ) ) | |
| 2 | 1 | exbidv | ⊢ ( 𝑤 = 𝑊 → ( ∃ 𝑓 𝑓 ( 𝐴 ( SPathsOn ‘ 𝐺 ) 𝐵 ) 𝑤 ↔ ∃ 𝑓 𝑓 ( 𝐴 ( SPathsOn ‘ 𝐺 ) 𝐵 ) 𝑊 ) ) | 
| 3 | eqid | ⊢ ( Vtx ‘ 𝐺 ) = ( Vtx ‘ 𝐺 ) | |
| 4 | 3 | iswspthsnon | ⊢ ( 𝐴 ( 𝑁 WSPathsNOn 𝐺 ) 𝐵 ) = { 𝑤 ∈ ( 𝐴 ( 𝑁 WWalksNOn 𝐺 ) 𝐵 ) ∣ ∃ 𝑓 𝑓 ( 𝐴 ( SPathsOn ‘ 𝐺 ) 𝐵 ) 𝑤 } | 
| 5 | 2 4 | elrab2 | ⊢ ( 𝑊 ∈ ( 𝐴 ( 𝑁 WSPathsNOn 𝐺 ) 𝐵 ) ↔ ( 𝑊 ∈ ( 𝐴 ( 𝑁 WWalksNOn 𝐺 ) 𝐵 ) ∧ ∃ 𝑓 𝑓 ( 𝐴 ( SPathsOn ‘ 𝐺 ) 𝐵 ) 𝑊 ) ) |