A363201 Number of free linear polycubes of size n, identifying rotations but not reflections.

1, 1, 2, 5, 16, 54, 212, 827, 3369, 13653, 56052, 229004, 939935, 3843859, 15753903, 64380796, 263475472, 1075780425, 4397161320, 17939394036, 73251877235, 298646347226, 1218453344740

Offset: 1

Author

Joerg Arndt and Márk Péter Légrádi, May 21 2023

Keywords

• nonn
• more

Comments

Linear polycubes have two end points with one neighbor, the remaining cubes all have two neighbors.

Additionally identifying reflections gives A363202.

The fixed version is A118339.

Links

• Arthur O'Dwyer, Polyomino strips, snakes, and ouroboroi, 2022.

Crossrefs

Cf. A363199 (tree-like polycubes).

Extensions

a(15)-a(23) from Arthur O'Dwyer added by Andrey Zabolotskiy, Jun 07 2023