178868domain: NAppears in sequencesNumber of ways to place zero or more nonadjacent 0,0 1,0 2,0 3,1 3,2 4,3 5,3 6,3 polyhexes in any orientation on a planar nXnXn triangular grid.at n=9A155396Number of chordless cycles in the complement of the n X n antelope graph.at n=15A370110