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 A211001 #26 Oct 02 2013 15:58:41 %S A211001 2,34,42,50,150,242,246,250,354,358,370,390,394,402,406,6570,6602, %T A211001 6606,6622,6626,6630,6634,6654,6658,6682,6686 %N A211001 Numbers congruent to 2 in the structure of A211000. %C A211001 The behavior seems to be as modular arithmetic but in a growing structure. The structure of A211000 looks like essentially a column of tangent circles of radius 1. The structure arises from the prime numbers A000040. For the number of circles at n-th stage see A211020. %Y A211001 Cf. A187210, A210838, A210841, A211000, A211002, A211003, A211010, A211011, A211020-A211023. %K A211001 nonn,more %O A211001 1,1 %A A211001 _Omar E. Pol_, Mar 30 2012