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

1,3

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

Table of n, a(n) for n=1..23.

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

Crossrefs

Cf. A363199 (tree-like polycubes).

Sequence in context: A148400 A052836 A108526 * A321470 A149968 A149969

Adjacent sequences: A363198 A363199 A363200 * A363202 A363203 A363204

Keyword

nonn,more

Author

Joerg Arndt and Márk Péter Légrádi, May 21 2023

Extensions

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

Status

approved