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 A118075 #6 Oct 05 2014 10:23:02 %S A118075 1,43,76,109,943,391,235,574,517,757,799,1039,9343,3481,1885,5923, %T A118075 3337,7375,5779,9817,7231,1369,9673,3811,1225,5263,3667,7705,5119, %U A118075 9157,7561,1699,10003,30043,34045,54085,58087,78127,72229,92269,96271,17311,11413 %N A118075 Start with 1 and repeatedly reverse the digits and add 42 to get the next term. %C A118075 After 245 steps enters a cycle of length 57. Sequence gives first 50 terms. Cycle : 985, 631, 178, 913, 361, 205, 544, 487, 826, 670, 118, 853, 400, 46, 106, 643, 388, 925, 571, 217, 754, 499, 1036, 6343, 3478, 8785, 5920, 337, 775, 619, 958, 901, 151, 193, 433, 376, 715, 559, 997, 841, 190, 133, 373, 415, 556, 697, 868, 880, 130, 73, 79, 139, 973, 421, 166, 703, 349, 985 ... %H A118075 N. J. A. Sloane and others, <a href="/wiki/Sequences_of_RADD_type">Sequences of RADD type</a>, OEIS wiki. %t A118075 NestList[FromDigits[Reverse[IntegerDigits[#]]]+42&,1,50] (* _Harvey P. Dale_, Oct 05 2014 *) %Y A118075 Cf. A117828, A117816, A117817. %K A118075 base,nonn %O A118075 1,2 %A A118075 Luc Stevens (lms022(AT)yahoo.com), May 11 2006 %E A118075 Corrected by _Harvey P. Dale_, Oct 05 2014