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A304198
Number of free tree-like 4d-polycubes of size n.
2
1, 1, 2, 6, 24, 122, 838, 6759, 61600, 600875, 6139448
OFFSET
1,3
COMMENTS
A free tree-like polycube of size n in four dimensions is a hyperface-connected set of n cells in the 4d-hypercubic lattice, up to translation, rotation and reflection, whose dual graph has no cycles.
LINKS
Alexandre Blondin Massé, Julien de Carufel, Alain Goupil, and Maxime Samson, Fully-leafed tree-like polyominoes and polycubes, In Combinatorial algorithms, volume 10765 of Lecture Notes of Computer Science, 28th International workshop, IWOCA 2017, Newcastle, NSW, Australia, Springer, 2018.
CROSSREFS
Cf. A191094 (fixed tree-like 4d-polycubes), A131482 (free tree-like polyominoes), A304196 (free tree-like 3d-polycubes).
Sequence in context: A104983 A375458 A144251 * A243806 A201158 A356634
KEYWORD
nonn,more
AUTHOR
Lotfi Bouallagui, May 07 2018
STATUS
approved