OFFSET
0,2
COMMENTS
In other words, number of independent vertex sets (and vertex covers) in the (n-1)-triangular grid graph. - Eric W. Weisstein, Jun 14 2017
Number of planar n X n X n binary triangular grids with no more than 1 one in any similarly oriented 2 X 2 X 2 subtriangle. - R. H. Hardin, Dec 27 2008
LINKS
Eric Weisstein's World of Mathematics, Independent Vertex Set
Eric Weisstein's World of Mathematics, Triangular Grid Graph
Eric Weisstein's World of Mathematics, Vertex Cover
CROSSREFS
KEYWORD
nonn,nice
AUTHOR
STATUS
approved