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

theorem Th26:
  len (k-polytope-seq(p)) = num-polytopes(p,k)
proof
  dom (k-polytope-seq(p)) = Seg (num-polytopes(p,k)) by Th25;
  hence thesis by FINSEQ_1:def 3;
end;
