A190477 Constant arising in lattice coverings of Nil space by congruent geodesic balls.

1, 4, 2, 9, 0, 0, 6, 1, 5

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

Table of n, a(n) for n=1..9.

Jeno Szirmai, On lattice coverings of Nil space by congruent geodesic balls, May 10, 2011.

Example

Approximately 1.42900615.

Crossrefs

Sequence in context: A084477 A046589 A072562 * A143311 A016696 A127470

Adjacent sequences: A190474 A190475 A190476 * A190478 A190479 A190480

Keyword

nonn,cons

Author

Jonathan Vos Post, May 10 2011

Status

approved