Degree-diameter problem $N(12,6)$

The largest possible number of vertices in a graph of maximum degree $12$ and diameter $6$.

Updates

• 2006-07-15 Lower bound: $359772$ (359,772)
  Pineda-Villavicencio, G., Gómez, J., Miller, M., & Pérez-Rosés, H. (2006). New largest graphs of diameter 6: (Extended Abstract). Electronic Notes in Discrete Mathematics, 24, 153-160.
  [via Table of the largest known graphs of a given diameter and maximal degree - Wikipedia]