OFFSET
0,3
COMMENTS
The Gram matrix [ 2, 1, 1; 1, 2, 1; 1, 1, 3 ] defines the same lattice.
This is the trigonal R lattice (the classical holotype) of dimension 3.
LINKS
John Cannon, Table of n, a(n) for n = 0..9999
G. Nebe and N. J. A. Sloane, Home page for this lattice
EXAMPLE
1 + 6*q^2 + 6*q^3 + 6*q^5 + 6*q^6 + 12*q^7 + 6*q^8 + 6*q^10 + 12*q^11 + 6*q^12 + ...
CROSSREFS
KEYWORD
nonn
AUTHOR
STATUS
approved