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 A117841 #22 May 29 2025 15:55:49 %S A117841 1,11,21,22,32,33,43,44,54,55,65,66,76,77,87,88,98,99,109,911,129,931, %T A117841 149,951,169,971,189,991,209,912,229,932,249,952,269,972,289,992,309, %U A117841 913,329,933,349,953,369,973,389,993,409,914,429,934,449,954,469,974,489,994,509 %N A117841 Start with 1 and repeatedly reverse the digits and add 10 to get the next term. %C A117841 This sequence (unlike A117828, say) never cycles. %C A117841 The operation can never generate a trailing zero and so is reversible. So it loops only if it returns to the start, which is impossible. - _Martin Fuller_, May 12 2006 %H A117841 Harvey P. Dale and N. J. A. Sloane, <a href="/A117841/b117841.txt">Table of n, a(n) for n = 1..20000</a> (First 1000 terms from Harvey P. Dale) %H A117841 N. J. A. Sloane and others, <a href="/wiki/Sequences_of_RADD_type">Sequences of RADD type</a>, OEIS wiki. %t A117841 NestList[FromDigits[Reverse[IntegerDigits[#]]]+10&,1,60] (* _Harvey P. Dale_, May 19 2012 *) %t A117841 NestList[IntegerReverse[#]+10&,1,60] (* _Harvey P. Dale_, May 29 2025 *) %Y A117841 Cf. A117830, A117828, A117816, A117817. %K A117841 nonn,base %O A117841 1,2 %A A117841 _David Applegate_, May 05 2006