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.

A365903 Number of partitions of [n] whose block minima sum to k, where k is chosen so as to maximize this number.

Original entry on oeis.org

1, 1, 1, 2, 4, 10, 29, 101, 367, 1562, 6891, 37871, 197930, 1121634, 6888085, 46190282, 323250987, 2349020516, 17897285514, 142512956148, 1178963284732, 10248806222398, 91421283039658, 847666112839362, 8100455404172267, 79925567946537362, 814508927747776069
Offset: 0

Views

Author

Alois P. Heinz, Dec 14 2023

Keywords

Crossrefs

Row maxima of A124327.
Cf. A367969.

Programs

  • Maple
    b:= proc(n, i, t, m) option remember; `if`(n=0, t^(m-i+1),
         `if`((i+m)*(m+1-i)/2n, 0, `if`(t=0, 0,
          t*b(n, i+1, t, m))+ b(n-i, i+1, t+1, m)))
        end:
    a:= n-> max(seq(b(k, 1, 0, n), k=0..n*(n+1)/2)):
    seq(a(n), n=0..26);
    # second Maple program:
    a:= proc(h) option remember; local b; b:=
          proc(n, m) option remember; `if`(n=0, 1,
            b(n-1, m)*m + expand(x^(h-n+1)*b(n-1, m+1)))
          end: forget(b); max(coeffs(b(h, 0)))
        end:
    seq(a(n), n=0..26);
  • Mathematica
    Q[1, t_, s_] := t*s;
    Q[n_, t_, s_] := Q[n, t, s] = s*D[Q[n-1, t, s], s] + s*t^n*Q[n-1, t, s] // Expand;
    P[n_, t_] := Module[{s}, Q[n, t, s] /. s -> 1];
    a[n_] := If[n == 0, 1, Module[{t}, CoefficientList[P[n, t], t] // Max]];
    Table[a[n], {n, 0, 26}] (* Jean-François Alcover, Oct 03 2024 *)