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.

A169740 a(n) = A030068(4n+3).

Original entry on oeis.org

2, 5, 9, 16, 23, 35, 48, 69, 87, 116, 145, 189, 228, 287, 345, 430, 501, 605, 704, 843, 965, 1136, 1299, 1523, 1716, 1981, 2231, 2566, 2863, 3261, 3638, 4137, 4569, 5140, 5675, 6367, 6984, 7781, 8531, 9490, 10339, 11423, 12440, 13721, 14875, 16328, 17697, 19409
Offset: 0

Views

Author

N. J. A. Sloane, May 02 2010

Keywords

Crossrefs

Programs

  • Mathematica
    f[1]=1; f[n_?EvenQ]:=f[n]=f[n/2]; f[n_?OddQ]:=f[n]=f[n-1]+f[n-2]; a[n_]:=f[4*n+3]; Table[a[n], {n, 0, 100}] (* Vincenzo Librandi, May 27 2019 *)
  • PARI
    {f(n) = if(n==1,1, if(n%2==0, f(n/2), f(n-1) + f(n-2)))};
    vector(50, n, n--; f(4*n+3)) \\ G. C. Greubel, May 29 2019
    
  • Sage
    def f(n):
        if (n==1): return 1
        elif (n%2==0): return f(n/2)
        else: return f(n-1) + f(n-2)
    [f(4*n+3) for n in (0..50)] # G. C. Greubel, May 29 2019