0,1

The hexagonal lattice is the familiar 2-dimensional lattice in which each point has 6 neighbors. This is sometimes called the triangular lattice.

I. Jensen, Table of n, a(n) for n = 0..53 (from link below)

I. Jensen, More terms

G. Nebe and N. J. A. Sloane, Home page for hexagonal (or triangular) lattice A2

Cf. A057374-A057405.

Sequence in context: A057382 A007270 A222896 * A109898 A223074 A192732

Adjacent sequences: A057384 A057385 A057386 * A057388 A057389 A057390

sign

N. J. A. Sloane, Aug 30 2000

approved