reserve x,y,y1,y2,z,e,s for set;
reserve alpha,beta,gamma for Ordinal;
reserve n,m,k for Nat;
reserve g,g0,g1,g2,gO,gL,gR,gLL,gLR,gRL,gRR for ConwayGame;

theorem Th24:
  g in the_Tree_of g
proof
  ex f being ConwayGameChain st f.1 = g & f.(len f) = g by Lm2;
  hence thesis by Def12;
end;
