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 A114612 #11 Feb 16 2025 08:32:59 %S A114612 9,18,27,36,45,54,63,69,72,78,81,87,90,96,99,108,114,117,120,126,135, %T A114612 144,153,156,162,171,180,189,198,207,213,216,225,234,243,252,255,261, %U A114612 270,279,288,297,306,312,315,324,333,342,351,354,360,369,378,387,396 %N A114612 Starting numbers for which the RATS sequence has eventual period 2. %C A114612 A114611(a(n)) = 2. - _Reinhard Zumkeller_, Mar 14 2012 %H A114612 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/RATSSequence.html">RATS Sequence</a> %Y A114612 Cf. A114611, A114612, A114613, A114614, A114615, A114616. %Y A114612 Cf. A066711, A036839. %K A114612 nonn,base %O A114612 1,1 %A A114612 _Eric W. Weisstein_, Dec 16 2005