Degree-diameter problem $N(6,10)$

The largest possible number of vertices in a graph of maximum degree $6$ and diameter $10$.

Updates

• 2008 Lower bound: $1253615$ (1,253,615)
  Loz, E., & Sirán, J. (2008). New record graphs in the degree-diameter problem. Australasian Journal of Combinatorics, 41, 63.
  [via Table of the largest known graphs of a given diameter and maximal degree - Wikipedia]