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 A190555 #8 Mar 30 2012 18:57:28 %S A190555 2,4,1,3,1,2,4,2,3,1,3,4,2,4,1,3,0,2,4,1,3,1,2,4,2,3,1,3,0,2,4,1,3,1, %T A190555 2,4,2,3,1,3,4,2,4,1,3,1,2,4,2,3,1,2,4,2,3,1,3,0,2,4,1,3,1,2,4,2,3,1, %U A190555 3,4,2,4,1,3,1,2,4,2,3,1,3,4,2,4,1,3,0,2,4,1,3,1,2,4,2,3,1,3,0,2,4,1,3,1,2,4,2,3,1,3,4,2,4,1,3,1,2,4,1,3,1,2,4,2,3,1,3,0 %N A190555 [(bn+c)r]-b[nr]-[cr], where (r,b,c)=(sqrt(2),4,2) and []=floor. %C A190555 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 A190555 Examples: %C A190555 (golden ratio,2,1): A190427-A190430 %C A190555 (sqrt(2),2,1): A190483-A190486 %C A190555 (sqrt(2),3,0): A190487-A190490 %C A190555 (sqrt(2),3,1): A190491-A190495 %C A190555 (sqrt(2),3,2): A190496-A190500 %t A190555 r = Sqrt[2]; b = 4; c = 2; %t A190555 f[n_] := Floor[(b*n + c)*r] - b*Floor[n*r] - Floor[c*r]; %t A190555 t = Table[f[n], {n, 1, 200}] (* A190555 *) %t A190555 Flatten[Position[t, 0]] (* A190556 *) %t A190555 Flatten[Position[t, 1]] (* A190557 *) %t A190555 Flatten[Position[t, 2]] (* A190558 *) %t A190555 Flatten[Position[t, 3]] (* A190559 *) %t A190555 Flatten[Position[t, 4]] (* A190486 *) %Y A190555 Cf. A190556-A190559, A190486. %K A190555 nonn %O A190555 1,1 %A A190555 _Clark Kimberling_, May 12 2011