OFFSET
0,1
COMMENTS
The hexagonal lattice is the familiar 2-dimensional lattice in which each point has 6 neighbors. This is sometimes called the triangular lattice.
LINKS
I. Jensen, Table of n, a(n) for n = 0..63 (from link below)
I. Jensen, More terms
G. Nebe and N. J. A. Sloane, Home page for hexagonal (or triangular) lattice A2
CROSSREFS
KEYWORD
sign
AUTHOR
N. J. A. Sloane, Aug 30 2000
STATUS
approved