OFFSET
1,2
COMMENTS
The Nil geometry is one of the eight 3-dimensional Thurston geometries, which can be derived from W. Heisenberg's real matrix group.
LINKS
Jeno Szirmai, On lattice coverings of Nil space by congruent geodesic balls, May 10, 2011.
EXAMPLE
Approximately 1.42900615.
CROSSREFS
KEYWORD
nonn,cons
AUTHOR
Jonathan Vos Post, May 10 2011
STATUS
approved