
theorem
  for G being _Graph
  holds G is edge-finite iff ex n being Nat st G is n-edge
proof
  let G be _Graph;
  hereby
    assume G is edge-finite;
    then reconsider n = card the_Edges_of G as Nat;
    take n;
    thus G is n-edge;
  end;
  thus thesis;
end;
