reserve G,G1,G2 for _Graph;
reserve W,W1,W2 for Walk of G;
reserve e,x,y,z for set;
reserve v for Vertex of G;
reserve n,m for Element of NAT;

theorem
  for m,n being odd Element of NAT, x being Element of NAT st m <= n & n
<= len W & W.m = W.n & x in dom W.remove(m,n) holds x in Seg m or m <= x & x <=
  len W.remove(m,n) by Lm34;
