TARDIS tight schedule, which led to Brachacki leaving the show due to disagreements with the production team and possibly a feeling that he had been given an impossible task. Despite his leaving the show and mixed reactions as to how the set looked (producer Verity Lambert liked it but director Waris Hussein did not), the basic design of the hexagonal console and wall roundels has persisted to the present day. In the Third Doctor serial "The Time Monster" (1972), the console room of the TARDIS was dramatically altered, including the wall roundels. This new set, designed by Tim Gleeson, was disliked
Hexagonal lattice term "honeycomb lattice" could mean a corresponding hexagonal lattice, or a structure which is not a lattice in the group sense, but e.g. one in the sense of a lattice model. A set of points forming the vertices of a honeycomb (without points at the centers) shows the honeycomb structure. It can be seen as the union of two offset triangular lattices, shown here red and blue. A triangular lattice itself can be divided into 3 offset triangular lattices, shown above in red, green and blue. A triangular lattice is also called an A2 lattice, A, and the union of