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
  ex lenWaa1 being even Element of NAT st lenWaa1 = len W - 1 & len W
  .edgeSeq() = lenWaa1 div 2 by Lm42;
