A206904 n+[nr/s]+[nt/s], where []=floor, r=3, s=sqrt(3), t=1/s.

2, 5, 9, 11, 14, 18, 21, 23, 27, 30, 33, 36, 39, 42, 45, 48, 51, 55, 57, 60, 64, 67, 69, 73, 76, 79, 82, 85, 88, 91, 94, 97, 101, 103, 106, 110, 113, 115, 119, 122, 125, 128, 131, 134, 137, 140, 143, 147, 149, 152, 156, 159, 161, 165, 168, 170, 174, 177

Offset

1,1

Comments

The sequences A206903, A206904, A206905 partition the positive integers. To generate them, jointly rank the sets {n/3}, {n/sqrt(3)}, {n*sqrt(3)} for n>=1. The positions of n/3 in the joint ranking form A206903, and likewise for the other sequences.

Links

Table of n, a(n) for n=1..58.

Mathematica

r = 3; s = Sqrt[3]; t = 1/s;
a[n_] := n + Floor[n*s/r] + Floor[n*t/r];
b[n_] := n + Floor[n*r/s] + Floor[n*t/s];
c[n_] := n + Floor[n*r/t] + Floor[n*s/t];
Table[a[n], {n, 1, 70}]  (* A206903 *)
Table[b[n], {n, 1, 70}]  (* A206904 *)
Table[c[n], {n, 1, 70}]  (* A206905 *)

Crossrefs

Cf. A206903, A206905.

Sequence in context: A069829 A022429 A020907 * A189472 A190369 A067568

Adjacent sequences: A206901 A206902 A206903 * A206905 A206906 A206907

Keyword

nonn

Author

Clark Kimberling, Feb 13 2012

Status

approved