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.

A071897 CONTINUANT transform of Catalan numbers 1, 2, 5, 14, 42, ...

Original entry on oeis.org

1, 3, 16, 227, 9550, 1260827, 540904333, 773494457017, 3760730590920987, 63165231778603354669, 3713231319097707398492821, 772396673211317543153892036521, 573813488532401034128124101329943721, 1534629746271367018386831539104008577227761
Offset: 1

Views

Author

N. J. A. Sloane, Jun 10 2002

Keywords

Programs

  • Maple
    a:= proc(n) option remember; `if`(n<0, 0,
          `if`(n=0, 1, binomial(2*n, n)/(n+1) *a(n-1) +a(n-2)))
        end:
    seq(a(n), n=1..20);  # Alois P. Heinz, Aug 06 2013
  • Mathematica
    a[n_] := a[n] = If[n<0, 0, If[n==0, 1, CatalanNumber[n]*a[n-1] + a[n-2]]]; Table[a[n], {n, 1, 20}] (* Jean-François Alcover, Feb 25 2017, translated from Maple *)