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 A083151 #13 Aug 11 2024 14:41:34 %S A083151 5,505,5555,505505,5005005005,55055055055,50155155155105, %T A083151 5464353998993534645,541025148469303964841520145, %U A083151 513016415223221833242338122322514610315,5130164152232218845439796446446979345488122322514610315 %N A083151 a(1) = 5, a(n) = smallest nontrivial palindromic multiple of a(n-1). a(n) is not equal to a(n-1) or a concatenation of a(n-1) with itself. %C A083151 Multiplier for a(9) larger than 1000000000. %H A083151 P. De Geest, <a href="https://www.worldofnumbers.com/em36.htm">WONplate 36</a> %Y A083151 Cf. A083152, A068666, A083147, A083149, A083153, A083155. %K A083151 nonn,base,more %O A083151 1,1 %A A083151 _Amarnath Murthy_ and Meenakshi Srikanth (menakan_s(AT)yahoo.com), Apr 25 2003 %E A083151 More terms from _Patrick De Geest_, Jun 05 2003 %E A083151 a(5)-a(9) corrected by _Giovanni Resta_, Sep 22 2019 %E A083151 a(10) from _David A. Corneth_, Sep 22 2019 %E A083151 a(11) from _Giovanni Resta_, Sep 24 2019