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.

A366614 Irregular triangular array, read by rows: row n gives the numbers max(p) - min(p), in nondecreasing order, where p ranges through the strict partitions p of n.

Original entry on oeis.org

0, 0, 0, 1, 0, 2, 0, 1, 3, 0, 2, 2, 4, 0, 1, 3, 3, 5, 0, 2, 3, 4, 4, 6, 0, 1, 2, 3, 4, 5, 5, 7, 0, 2, 3, 3, 4, 4, 5, 6, 6, 8, 0, 1, 3, 3, 4, 4, 5, 5, 6, 7, 7, 9, 0, 2, 2, 4, 4, 4, 5, 5, 5, 6, 6, 7, 8, 8, 10, 0, 1, 3, 3, 4, 4, 5, 5, 5, 6, 6, 6, 7, 7, 8, 9, 9
Offset: 1

Views

Author

Clark Kimberling, Oct 25 2023

Keywords

Examples

			First twelve rows:
     0
     0
     0   1
     0   2
     0   1   3
     0   2   2   4
     0   1   3   3   5
     0   2   3   4   4   6
     0   1   2   3   4   5   5   7
     0   2   3   3   4   4   5   6   6   8
     0   1   3   3   4   4   5   5   6   7   7   9
     0   2   2   4   4   4   5   5   5   6   6   7   8   8   10
The strict partitions p of 8 are 8, 71, 62, 53, 521, 431, for which max(p)-min(p) are the numbers 0, 6, 4, 2, 4, 3, or, in nondecreasing order, 0, 2, 3, 4, 4, 6, as in row 8.
		

Crossrefs

Cf. A000009 (strict partitions), A117454 (frequencies).

Programs

  • Mathematica
    z = 20; d[n_] := d[n] = Select[IntegerPartitions[n], DeleteDuplicates[#] == # &];
    p[n_, k_] := p[n, k] = d[n][[k]];
    t = Table[Max[p[n, k]] - Min[p[n, k]], {n, 1, z}, {k, 1, PartitionsQ[n]}]
    m = Map[Sort, t]
    Column[m]
    Flatten[m]