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.
%I A206906 #8 Mar 30 2012 18:58:12
%S A206906 7,15,23,30,38,47,55,62,70,78,87,94,102,110,117,126,134,142,149,157,
%T A206906 166,174,181,189,197,206,213,221,229,236,245,253,261,268,276,285,293,
%U A206906 300,308,316,325,332,340,348,355,364,372,380,387,395,404,412,419
%N A206906 n+[ns/r]+[nt/r], where []=floor, r=1/3, s=sqrt(3), t=1/s.
%C A206906 The sequences A206906, A206907, A206908 partition the positive integers. To generate them, jointly rank the sets {3n}, {n/sqrt(3)}, {n*sqrt(3)} for n>=1. The positions of 3n in the joint ranking form A206906, and likewise for the other sequences.
%t A206906 r = 1/3; s = Sqrt[3]; t = 1/s;
%t A206906 a[n_] := n + Floor[n*s/r] + Floor[n*t/r];
%t A206906 b[n_] := n + Floor[n*r/s] + Floor[n*t/s];
%t A206906 c[n_] := n + Floor[n*r/t] + Floor[n*s/t];
%t A206906 Table[a[n], {n, 1, 70}] (* A206906 *)
%t A206906 Table[b[n], {n, 1, 80}] (* A206907 *)
%t A206906 Table[c[n], {n, 1, 70}] (* A206908 *)
%Y A206906 Cf. A206903.
%K A206906 nonn
%O A206906 1,1
%A A206906 _Clark Kimberling_, Feb 13 2012