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 A190688 #6 Mar 30 2012 18:57:28 %S A190688 2,1,1,3,2,1,0,3,2,1,0,2,2,1,3,2,1,0,3,2,1,0,2,2,1,0,2,1,1,3,2,1,0,3, %T A190688 2,1,0,2,2,1,0,2,1,1,3,2,1,0,3,2,1,0,2,2,1,3,2,1,1,3,2,1,0,3,2,1,0,2, %U A190688 1,1,3,2,1,0,3,2,1,0,2,2,1,0,2,1,1,3,2,1,0,3,2,1,0,2,2,1,0,2,1,1,3,2,1,0,3,2,1,0,2,2,1,3,2,1,1,3,2,1,0,3,2,1,0,2,1,1,3,2,1,0,3,2 %N A190688 [(bn+c)r]-b[nr]-[cr], where (r,b,c)=(sqrt(3),3,2) and [ ]=floor. %C A190688 Write a(n)=[(bn+c)r]-b[nr]-[cr]. If r>0 and b and c are integers satisfying b>=2 and 0<=c<=b-1, then 0<=a(n)<=b. The positions of 0 in the sequence a are of interest, as are the position sequences for 1,2,...,b. These b+1 position sequences comprise a partition of the positive integers. %C A190688 Examples: %C A190688 (golden ratio,2,1): A190427-A190430 %C A190688 (sqrt(2),2,0): A190480-A190482 %C A190688 (sqrt(2),2,1): A190483-A190486 %C A190688 (sqrt(2),3,0): A190487-A190490 %C A190688 (sqrt(2),3,1): A190491-A190495 %C A190688 (sqrt(2),3,2): A190496-A190500 %C A190688 (sqrt(2),4,c): A190544-A190566 %t A190688 r = Sqrt[3]; b = 3; c = 2; %t A190688 f[n_] := Floor[(b*n + c)*r] - b*Floor[n*r] - Floor[c*r]; %t A190688 t = Table[f[n], {n, 1, 200}] (* A190688 *) %t A190688 Flatten[Position[t, 0]] (* A190689 *) %t A190688 Flatten[Position[t, 1]] (* A190690 *) %t A190688 Flatten[Position[t, 2]] (* A190691 *) %t A190688 Flatten[Position[t, 3]] (* A190692 *) %Y A190688 Cf. A190689-A190692. %K A190688 nonn %O A190688 1,1 %A A190688 _Clark Kimberling_, May 17 2011