OFFSET
0,2
COMMENTS
The hexagonal lattice is the familiar 2-dimensional lattice in which each point has 6 neighbors. This is sometimes called the triangular lattice. - Sean A. Irvine, Jun 22 2022
LINKS
Sean A. Irvine, Table of n, a(n) for n = 0..250
C. Banderier, Analytic combinatorics of random walks and planar maps, PhD Thesis, 2001.
Sean A. Irvine, Java program (github)
FORMULA
a(n) ~ (sqrt(3) - 1) * 2^n * 3^(n+1) / (Pi*n). - Vaclav Kotesovec, Apr 30 2024
CROSSREFS
KEYWORD
nonn
AUTHOR
Cyril Banderier, Oct 12 2000
EXTENSIONS
Title corrected by Sean A. Irvine, Jun 22 2022
STATUS
approved