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 A031881 #20 Nov 15 2019 06:28:06 %S A031881 3,7,151,727,787,10501,13831,18181,30103,70207,72727,77377,78487, %T A031881 93139,94849,96469,96769,98689,1008001,1062601,1160611,1190911, %U A031881 1253521,1327231,1409041,1447441,1463641,1490941,1640461,1670761,1684861 %N A031881 Lucky numbers that are both palindromic and prime. %H A031881 Amiram Eldar, <a href="/A031881/b031881.txt">Table of n, a(n) for n = 1..426</a> (terms below 10^9, terms 1..66 from Robert G. Wilson v) %t A031881 lst = Range[1, 10^6, 2]; i = 2; While[lst[[i]] <= Length[lst], del = Partition[Range[lst[[i]], Length[lst], lst[[i]]], 1]; lst = Delete[lst, del]; i++ ]; lst = Select[lst, PrimeQ[ # ] &]; lst = Select[lst, (ToString[ # ] == StringReverse[ToString[ # ]]) &] %Y A031881 Cf. A000040, A000959, A002113, A002385. %K A031881 nonn,base %O A031881 1,1 %A A031881 _Patrick De Geest_ %E A031881 Corrected and extended by Vit Planocka (planocka(AT)mistral.cz), Jan 31 2003