cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A385580 a(n) is the number of ways to partition an n X n X n cube with four noncongruent cuboids of different volumes.

Original entry on oeis.org

0, 0, 4, 11, 47, 77, 183, 259, 457, 599, 941, 1120, 1668, 1986, 2637, 3125, 4079, 4622, 5868, 6530, 8061, 9028, 10874, 11856, 14148, 15522, 18074, 19583, 22739, 24292, 28065, 30105, 34071, 36544, 40885, 43520, 48888, 51912, 57512, 60666, 67331, 70777, 78078
Offset: 1

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Author

Janaka Rodrigo, Aug 12 2025

Keywords

Comments

Alternatively, a(n) is the number of ways to decompose (n,n,n) triplet into geometrically feasible four distinct unordered triplets of the form (x,y,z) with no pairs of triplets having equal value for the product x*y*z.

Examples

			There are A384311(4) = 12 different ways to decompose a 4 X 4 X 4 cube into four noncongruent cuboids, but of those 12 ways, one partition {(4,2,1), (4,2,2), (4,3,2), (4,4,1)} contains two cuboids of volume 16 ((4,2,2) and (4,4,1)) which needs to be excluded. Therefore a(4) = 12-1 = 11.
		

Crossrefs

Cf. A384311.

Formula

Conjecture: a(p) = A384311(p) for any prime p.