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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.

A326370 Number of condensations to convert all the partitions of n to strict partitions of n.

Original entry on oeis.org

0, 1, 1, 2, 1, 2, 2, 3, 2, 2, 3, 3, 3, 3, 3, 4, 3, 3, 4, 3, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 5, 4, 4, 5, 4, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 6, 5, 5, 6, 5, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6
Offset: 1

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Author

Clark Kimberling, Jul 06 2019

Keywords

Comments

Suppose that p is a partition of n. Let x(1), x(2), ..., x(k) be the distinct parts of p, and let m(i) be the multiplicity of x(i) in p. The partition {m(1)*x(1), m(2)*x(2), ..., x(k)*m(k)} of n is called the condensation of p.

Examples

			The condensation of [4, 2, 1, 1] is [4, 2, 2], of which the condensation is [4, 4], of which condensation is [8]; thus, a total of three condensations. This is maximal for the partitions of 8, so that a(8) = 3. See A239312.
		

Crossrefs

Programs

  • Mathematica
    f[m_] := Table[Tally[m][[h]][[1]]*Tally[m][[h]][[2]], {h, 1, Length[Tally[m]]}];
    m[n_, k_] := IntegerPartitions[n][[k]];
    q[n_, k_] := -2 + Length[FixedPointList[f, m[n, k]]];
    a[n_] := Max[Table[q[n, k], {k, 1, PartitionsP[n]}]];
    Table[a[n], {n, 1, 30}]
  • PARI
    See Links section.

Extensions

More terms from Rémy Sigrist, Jul 07 2019