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.

A180682 a(n) is the largest path count within the (right-aligned Ferrers plots of the) partitions of n.

Original entry on oeis.org

1, 1, 1, 2, 2, 3, 3, 5, 6, 7, 9, 10, 14, 16, 19, 23, 28, 32, 42, 47, 56, 66, 76, 90, 107, 132, 146, 174, 202, 230, 268, 314, 359, 429, 471, 561, 645, 735, 847, 979, 1094, 1247, 1430, 1593, 1859, 2123, 2420, 2768, 3172, 3503, 4019, 4481, 5096, 5691, 6384, 7168, 8151
Offset: 1

Views

Author

Wouter Meeussen, Sep 16 2010

Keywords

Examples

			a(13)=14 because the partition of 13 with largest path count is 4432, producing {1,1,1,1}, {1,2,3,4}, {2,5,9}, {5,14} with closing value 14.
		

Programs

  • Mathematica
    pathcount[p_] := Block[{ferr = (0*Range[#1] &) /@ p}, Last[Fold[Rest[FoldList[Plus, 0, Drop[#1, Length[#1] - Length[#2]] + #2]] &, 1 + First[ferr], Rest[ferr]]]]; f[n_] := Block[{k = mx = 1}, While[k < n + 1, m = Max[ pathcount /@ IntegerPartitions[n, {k}]]; If[m > mx, mx = m]; k++]; mx]; k = 1; lst = {}; While[k < 58, a = f@ k; Print[{k, a}]; AppendTo[lst, a]; k++ ]; lst

Extensions

a(37) onwards from Robert G. Wilson v, Sep 19 2010