A363201 - OEIS

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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

(list; graph; refs; listen; history; text; internal format)

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).