Description: The set of circuits (in an undirected graph). (Contributed by Alexander van der Vekens, 30-Oct-2017) (Revised by AV, 31-Jan-2021)
Ref | Expression | ||
---|---|---|---|
Assertion | crcts | ⊢ ( Circuits ‘ 𝐺 ) = { 〈 𝑓 , 𝑝 〉 ∣ ( 𝑓 ( Trails ‘ 𝐺 ) 𝑝 ∧ ( 𝑝 ‘ 0 ) = ( 𝑝 ‘ ( ♯ ‘ 𝑓 ) ) ) } |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | biidd | ⊢ ( 𝑔 = 𝐺 → ( ( 𝑝 ‘ 0 ) = ( 𝑝 ‘ ( ♯ ‘ 𝑓 ) ) ↔ ( 𝑝 ‘ 0 ) = ( 𝑝 ‘ ( ♯ ‘ 𝑓 ) ) ) ) | |
2 | df-crcts | ⊢ Circuits = ( 𝑔 ∈ V ↦ { 〈 𝑓 , 𝑝 〉 ∣ ( 𝑓 ( Trails ‘ 𝑔 ) 𝑝 ∧ ( 𝑝 ‘ 0 ) = ( 𝑝 ‘ ( ♯ ‘ 𝑓 ) ) ) } ) | |
3 | 1 2 | fvmptopab | ⊢ ( Circuits ‘ 𝐺 ) = { 〈 𝑓 , 𝑝 〉 ∣ ( 𝑓 ( Trails ‘ 𝐺 ) 𝑝 ∧ ( 𝑝 ‘ 0 ) = ( 𝑝 ‘ ( ♯ ‘ 𝑓 ) ) ) } |