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.

A290351 Euler transform of the Bell numbers (A000110).

Original entry on oeis.org

1, 1, 3, 8, 26, 88, 340, 1411, 6417, 31474, 166242, 939646, 5659613, 36158227, 244049562, 1733702757, 12919475840, 100690425442, 818554392962, 6924577964036, 60828588178031, 553821749290234, 5217264062756556, 50776256646839085, 509823607380230570
Offset: 0

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Author

Alois P. Heinz, Jul 28 2017

Keywords

Crossrefs

Programs

  • Maple
    b:= proc(n) option remember; `if`(n=0, 1, add(
          b(n-j)*binomial(n-1, j-1), j=1..n))
        end:
    a:= proc(n) option remember; `if`(n=0, 1, add(add(d*
          b(d), d=numtheory[divisors](j))*a(n-j), j=1..n)/n)
        end:
    seq(a(n), n=0..30);
  • Mathematica
    b[n_]:=b[n]=If[n==0, 1, Sum[b[n - j] Binomial[n - 1, j - 1], {j, n}]]; a[n_]:=a[n]=If[n==0, 1, Sum[Sum[d*b[d], {d, Divisors[j]}] a[n - j], {j, n}]/n]; Table[a[n], {n, 0, 50}] (* Indranil Ghosh, Jul 28 2017, after Maple code *)