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.

A276881 Sums-complement of the Beatty sequence for 1 + sqrt(5).

Original entry on oeis.org

1, 2, 5, 8, 11, 14, 15, 18, 21, 24, 27, 28, 31, 34, 37, 40, 41, 44, 47, 50, 53, 54, 57, 60, 63, 66, 69, 70, 73, 76, 79, 82, 83, 86, 89, 92, 95, 96, 99, 102, 105, 108, 109, 112, 115, 118, 121, 124, 125, 128, 131, 134, 137, 138, 141, 144, 147, 150, 151, 154
Offset: 1

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Author

Clark Kimberling, Sep 27 2016

Keywords

Comments

See A276871 for a definition of sums-complement and guide to related sequences.

Examples

			The Beatty sequence for 1 + sqrt(5) is A276854 = (0,3,6,9,12,16,19,...), with difference sequence s = A276863 = (3,3,3,3,4,3,3,3,4,3,3,3,4,3,3,3,4,...).  The sums s(j)+s(j+1)+...+s(k) include (3,4,6,7,9,10,12,13,...), with complement (1,2,5,8,11,14,15,,...).
		

Crossrefs

Programs

  • Mathematica
    z = 500; r = 1+ Sqrt[5]; b = Table[Floor[k*r], {k, 0, z}]; (* A276854 *)
    t = Differences[b]; (* A276863 *)
    c[k_, n_] := Sum[t[[i]], {i, n, n + k - 1}];
    u[k_] := Union[Table[c[k, n], {n, 1, z - k + 1}]];
    w = Flatten[Table[u[k], {k, 1, z}]]; Complement[Range[Max[w]], w]  (* A276881 *)