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.

A294335 Number of compositions (ordered partitions) of n into cubes dividing n.

Original entry on oeis.org

1, 1, 1, 1, 1, 1, 1, 1, 2, 1, 1, 1, 1, 1, 1, 1, 11, 1, 1, 1, 1, 1, 1, 1, 64, 1, 1, 2, 1, 1, 1, 1, 345, 1, 1, 1, 1, 1, 1, 1, 1824, 1, 1, 1, 1, 1, 1, 1, 9661, 1, 1, 1, 1, 1, 30, 1, 51284, 1, 1, 1, 1, 1, 1, 1, 272334, 1, 1, 1, 1, 1, 1, 1, 1445995, 1, 1, 1, 1, 1, 1, 1, 7677250, 463, 1, 1, 1, 1
Offset: 0

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Author

Ilya Gutkovskiy, Oct 28 2017

Keywords

Examples

			a(16) = 11 because 16 has 5 divisors {1, 2, 4, 8, 16} among which 2 are cubes {1, 8} therefore we have [8, 8], [8, 1, 1, 1, 1, 1, 1, 1, 1], [1, 8, 1, 1, 1, 1, 1, 1, 1], [1, 1, 8, 1, 1, 1, 1, 1, 1], [1, 1, 1, 8, 1, 1, 1, 1, 1], [1, 1, 1, 1, 8, 1, 1, 1, 1], [1, 1, 1, 1, 1, 8, 1, 1, 1], [1, 1, 1, 1, 1, 1, 8, 1, 1], [1, 1, 1, 1, 1, 1, 1, 8, 1], [1, 1, 1, 1, 1, 1, 1, 1, 8] and [1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1].
		

Crossrefs

Programs

  • Mathematica
    Table[SeriesCoefficient[1/(1 - Sum[Boole[Mod[n, k] == 0 && IntegerQ[k^(1/3)]] x^k, {k, 1, n}]), {x, 0, n}], {n, 0, 85}]

Formula

a(m)=1 when m is cubefree (A004709) and a(m)<>1 when m is not cubefree (A046099). - Michel Marcus, Oct 29 2017