Metamath Proof Explorer


Theorem subgrcycl

Description: If a cycle exists in a subgraph of a graph G , then that cycle also exists in G . (Contributed by BTernaryTau, 23-Oct-2023)

Ref Expression
Assertion subgrcycl ( 𝑆 SubGraph 𝐺 → ( 𝐹 ( Cycles ‘ 𝑆 ) 𝑃𝐹 ( Cycles ‘ 𝐺 ) 𝑃 ) )

Proof

Step Hyp Ref Expression
1 subgrpth ( 𝑆 SubGraph 𝐺 → ( 𝐹 ( Paths ‘ 𝑆 ) 𝑃𝐹 ( Paths ‘ 𝐺 ) 𝑃 ) )
2 1 anim1d ( 𝑆 SubGraph 𝐺 → ( ( 𝐹 ( Paths ‘ 𝑆 ) 𝑃 ∧ ( 𝑃 ‘ 0 ) = ( 𝑃 ‘ ( ♯ ‘ 𝐹 ) ) ) → ( 𝐹 ( Paths ‘ 𝐺 ) 𝑃 ∧ ( 𝑃 ‘ 0 ) = ( 𝑃 ‘ ( ♯ ‘ 𝐹 ) ) ) ) )
3 iscycl ( 𝐹 ( Cycles ‘ 𝑆 ) 𝑃 ↔ ( 𝐹 ( Paths ‘ 𝑆 ) 𝑃 ∧ ( 𝑃 ‘ 0 ) = ( 𝑃 ‘ ( ♯ ‘ 𝐹 ) ) ) )
4 iscycl ( 𝐹 ( Cycles ‘ 𝐺 ) 𝑃 ↔ ( 𝐹 ( Paths ‘ 𝐺 ) 𝑃 ∧ ( 𝑃 ‘ 0 ) = ( 𝑃 ‘ ( ♯ ‘ 𝐹 ) ) ) )
5 2 3 4 3imtr4g ( 𝑆 SubGraph 𝐺 → ( 𝐹 ( Cycles ‘ 𝑆 ) 𝑃𝐹 ( Cycles ‘ 𝐺 ) 𝑃 ) )