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.

A293025 E.g.f.: exp(exp(x) - Sum_{i=0..5} x^i/i!).

Original entry on oeis.org

1, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 463, 1717, 4720, 11441, 25884, 56135, 2977313, 23524737, 125212889, 552517341, 2183244857, 8025931950, 124257251233, 1468856487536, 12433365625566, 85767520652726, 518324768774506, 2858925345803536, 26181976719735061
Offset: 0

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Author

Seiichi Manyama, Sep 28 2017

Keywords

Comments

a(n) is the number of set partitions of [n] into blocks of size > 5.

Crossrefs

Column k=5 of A293024.

Programs

  • Maple
    a:= proc(n) option remember; `if`(n=0, 1, add(
          a(n-j)*binomial(n-1, j-1), j=6..n))
        end:
    seq(a(n), n=0..35);  # Alois P. Heinz, Sep 28 2017
  • Mathematica
    m = 31;
    Exp[Exp[x] - Sum[x^i/i!, {i, 0, 5}]] + O[x]^m // CoefficientList[#, x]& // (# Range[0, m-1]!)& (* Jean-François Alcover, Mar 08 2021 *)
  • PARI
    my(x='x+O('x^66)); Vec(serlaplace(exp(exp(x)-1-x-x^2/2-x^3/6-x^4/24-x^5/120)))

Formula

E.g.f.: Product_{i>5} exp(x^i/i!).