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.

A184480 Lower s-Wythoff sequence, where s(n)=3n. Complement of A001956.

Original entry on oeis.org

1, 2, 3, 5, 6, 7, 9, 10, 11, 13, 14, 15, 16, 18, 19, 20, 22, 23, 24, 26, 27, 28, 29, 31, 32, 33, 35, 36, 37, 39, 40, 41, 42, 44, 45, 46, 48, 49, 50, 52, 53, 54, 56, 57, 58, 59, 61, 62, 63, 65, 66, 67, 69, 70, 71, 72, 74, 75, 76, 78, 79, 80, 82, 83, 84, 85, 87, 88, 89, 91, 92, 93, 95, 96, 97, 99, 100, 101, 102, 104, 105, 106, 108, 109, 110, 112, 113, 114, 115, 117, 118, 119, 121, 122, 123, 125, 126, 127, 128, 130, 131, 132, 134, 135, 136, 138, 139, 140, 142, 143, 144, 145, 147, 148, 149, 151, 152, 153, 155, 156
Offset: 1

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Author

Clark Kimberling, Jan 15 2011

Keywords

Comments

A184480(n)=A001955(n) for n<43.
See A184117 for the definition of lower and upper Wythoff sequences.

Crossrefs

Cf. A184117.

Programs

  • Mathematica
    k=3; r=0; d=Sqrt[4+k^2];
    a[n_]:=Floor[(1/2)(d+2-k)(n+r/(d+2))];
    b[n_]:=Floor[(1/2)(d+2+k)(n-r/(d+2))];
    Table[a[n],{n,120}]
    Table[b[n],{n,120}]

Formula

a(n)=floor[n*(-1+sqrt(13))/2].
b(n)=floor[n*(5+sqrt(13))/2]=A001956(n).