Metamath Proof Explorer


Theorem isubgrusgr

Description: An induced subgraph of a simple graph is a simple graph. (Contributed by AV, 15-May-2025)

Ref Expression
Hypothesis isubgrupgr.v ⊢ 𝑉 = ( Vtx ‘ 𝐺 )
Assertion isubgrusgr ( ( 𝐺 ∈ USGraph ∧ 𝑆 ⊆ 𝑉 ) → ( 𝐺 ISubGr 𝑆 ) ∈ USGraph )

Proof

Step Hyp Ref Expression
1 isubgrupgr.v ⊢ 𝑉 = ( Vtx ‘ 𝐺 )
2 usgruhgr ⊢ ( 𝐺 ∈ USGraph → 𝐺 ∈ UHGraph )
3 1 isubgrsubgr ⊢ ( ( 𝐺 ∈ UHGraph ∧ 𝑆 ⊆ 𝑉 ) → ( 𝐺 ISubGr 𝑆 ) SubGraph 𝐺 )
4 2 3 sylan ⊢ ( ( 𝐺 ∈ USGraph ∧ 𝑆 ⊆ 𝑉 ) → ( 𝐺 ISubGr 𝑆 ) SubGraph 𝐺 )
5 subusgr ⊢ ( ( 𝐺 ∈ USGraph ∧ ( 𝐺 ISubGr 𝑆 ) SubGraph 𝐺 ) → ( 𝐺 ISubGr 𝑆 ) ∈ USGraph )
6 4 5 syldan ⊢ ( ( 𝐺 ∈ USGraph ∧ 𝑆 ⊆ 𝑉 ) → ( 𝐺 ISubGr 𝑆 ) ∈ USGraph )