A363202 Number of free linear polycubes of size n, identifying rotations and reflections.

1, 1, 2, 4, 12, 34, 125, 450, 1780, 7021, 28521, 115553, 472578, 1927634, 7890893, 32221475, 131812746, 538059836, 2198986587, 8970624060, 36628143111, 149328243327, 609238673619

Offset

1,3

Comments

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

Identifying rotations but not reflections gives A363201.

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. A304196 (tree-like polycubes), A363208, A363209, A363210.

Sequence in context: A148203 A240904 A245310 * A215953 A209027 A069727

Adjacent sequences: A363199 A363200 A363201 * A363203 A363204 A363205

Keyword

nonn,more

Author

Joerg Arndt and Márk Péter Légrádi, May 21 2023

Extensions

a(17)-a(22) from Arthur O'Dwyer added by Andrey Zabolotskiy, Jun 07 2023

a(23) added by Arthur O'Dwyer, Aug 11 2023

Status

approved