1286655domain: NAppears in sequencesThe number of ways that a straight line segment of length n, marked into n equal units, can be surrounded in a plane by one layer of regular polygons of unit edge that fit together without any gaps or overlaps, such that every polygon shares either a vertex or an exact unit edge with the segment. ("Line wreaths of length n.") Ways that differ by reflection or rotation are not counted as different.at n=12A158091