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 A118613 #13 Apr 20 2025 15:29:09
%S A118613 1,28,109,928,856,685,613,343,370,100,28,109,928,856,685,613,343,370,
%T A118613 100,28,109,928,856,685,613,343,370,100,28,109,928,856,685,613,343,
%U A118613 370,100,28,109,928,856,685,613,343,370,100,28,109,928,856,685,613,343,370
%N A118613 Start with 1 and repeatedly reverse the digits and add 27 to get the next term.
%C A118613 After 1 step enters a cycle of length 9.
%H A118613 Harvey P. Dale, <a href="/A118613/b118613.txt">Table of n, a(n) for n = 1..1000</a>
%H A118613 N. J. A. Sloane and others, <a href="/wiki/Sequences_of_RADD_type">Sequences of RADD type</a>, OEIS wiki.
%H A118613 <a href="/index/Rec#order_09">Index entries for linear recurrences with constant coefficients</a>, signature (0, 0, 0, 0, 0, 0, 0, 0, 1).
%t A118613 NestList[IntegerReverse[#]+27&,1,60] (* or *) PadRight[{1},60,{100,28,109,928,856,685,613,343,370}] (* _Harvey P. Dale_, Apr 20 2025 *)
%Y A118613 Cf. A117828, A117816, A117817.
%K A118613 base,nonn
%O A118613 1,2
%A A118613 Luc Stevens (lms022(AT)yahoo.com), May 08 2006