reserve n for Nat,
  k for Integer;
reserve p for polyhedron,
  k for Integer,
  n for Nat;

theorem Th54:
  [#]((-1)-chain-space(p)) = { {}, {{}} }
proof
  (-1)-polytopes(p) = {{}} by Def5;
  hence thesis by ZFMISC_1:24;
end;
