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.

A270763 Total sum of the sizes of all blocks with maximal element 9 in all set partitions of {1,2,...,n}.

Original entry on oeis.org

54267, 230884, 1090335, 5624233, 31336468, 187018111, 1187718179, 7984210898, 56562256041, 420709044049, 3275003008250, 26608043757997, 225076163325759, 1977999456151260, 18024710156370739, 170022295940977197, 1657528265315075476, 16676976427179730819
Offset: 9

Views

Author

Alois P. Heinz, Mar 22 2016

Keywords

Crossrefs

Column k=9 of A270701.
A diagonal of A270702.

Programs

  • Mathematica
    b[n_, m_, t_] := b[n, m, t] = If[n == 0, {1, 0}, Sum[If[t == 1 && j != m + 1, 0, Function[p, p + If[j == -t || t == 1 && j == m + 1, {0, p[[1]]}, 0]][b[n - 1, Max[m, j], If[t == 1 && j == m + 1, -j, If[t < 0, t, If[t > 0, t - 1, 0]]]]]], {j, 1, m + 1}]];
    a[n_] := b[n, 0, Max[0, 1 + n - 9]][[2]];
    Array[a, 24, 9] (* Jean-François Alcover, May 26 2018, from Maple code for A270701 *)