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.

A174111 Denominators of the image of a modified Bernoulli-number sequence under the Akiyama-Tanigawa transform.

Original entry on oeis.org

2, 3, 2, 15, 6, 7, 6, 15, 10, 33, 6, 455, 210, 3, 2, 255, 30, 133, 42, 33, 110, 69, 6, 455, 546, 3, 2, 435, 30, 2387, 462
Offset: 0

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Author

Paul Curtz, Mar 08 2010

Keywords

Comments

The image of the sequence A164555(k)/A027642(k), k>=0, under the Takiyama-Tanigawa
transform is
1/2, 2/3, 1/2, 2/15, -1/6, -1/7, 1/6, 4/15, -3/10, -25/33, 5/6, 1382/455, -691/210, -49/3, 35/2, 28936/255, -3617/30, -131601/133, 43867/42, 349222/33, ...
The current sequence contains the denominators of this image.

Crossrefs

Cf. A174110 (numerators), A164661.

Programs

  • Maple
    read("transforms3") ;
    A174111 := proc(n) Lin := [bernoulli(0),-bernoulli(1),seq(bernoulli(k),k=2..n+1)] ; AKIYATANI(Lin) ; denom(op(n+1,%)) ; end proc:
  • Mathematica
    b[0]=0; b[1]=1; b[2]=1/2; b[n_] := BernoulliB[n-1]; a[0, m_] := b[m+1]; a[n_, m_] := a[n, m] = (m+1)*(a[n-1, m] - a[n-1, m+1]); Table[a[1, m], {m, 0, 30}] // Denominator  (* Jean-François Alcover, Aug 09 2012 *)