Metamath Proof Explorer


Theorem 0wlk0

Description: There is no walk for the empty set, i.e. in a null graph. (Contributed by Alexander van der Vekens, 2-Sep-2018) (Revised by AV, 5-Mar-2021)

Ref Expression
Assertion 0wlk0 ( Walks ‘ ∅ ) = ∅

Proof

Step Hyp Ref Expression
1 vtxval0 ( Vtx ‘ ∅ ) = ∅
2 g0wlk0 ( ( Vtx ‘ ∅ ) = ∅ → ( Walks ‘ ∅ ) = ∅ )
3 1 2 ax-mp ( Walks ‘ ∅ ) = ∅