OFFSET
1,15
COMMENTS
See A057557 for N x N x N, where N={1,2,3,...}.
The triples are sorted first according to their sum, then lexicographically. - Pontus von Brömssen, Aug 16 2023
LINKS
Alois P. Heinz, Table of n, a(n) for n = 1..10962
EXAMPLE
Flatten the list of ordered lattice points, (0,0,0) < (0,0,1) < (0,1,0) < ... to 0,0,0, 0,0,1, 0,1,0, ...
As a three-column array:
0 0 0
0 0 1
0 1 0
1 0 0
0 0 2
0 1 1
0 2 0
1 0 1
1 1 0
2 0 0
0 0 3
0 1 2
0 2 1
0 3 0
1 0 2
1 1 1
1 2 0
2 0 1
2 1 0
3 0 0
...
MATHEMATICA
lexicographicLattice[{dim_, maxHeight_}]:= Flatten[Array[Sort@Flatten[(Permutations[#1]&)/@IntegerPartitions[#1+dim-1, {dim}], 1]&, maxHeight], 1]; Flatten@lexicographicLattice[{3, 6}]-1
(* Peter J. C. Moses, Feb 10 2011 *)
CROSSREFS
KEYWORD
nonn,tabf
AUTHOR
Clark Kimberling, Sep 07 2000
EXTENSIONS
Extended by Clark Kimberling, Feb 10 2011
STATUS
approved