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 A275220 #15 Aug 19 2016 02:27:03 %S A275220 5,17,65,121,562,1432,1477,4369,35101,35101,83161,83161,291721,291721, %T A275220 720721,887041,1496881,1670761,3341521,3341521,5654881,7207201, %U A275220 7761601,10810801,12252241,15135121,21621601,28274401,28274401,41081041,41081041,41081041 %N A275220 a(n) is the smallest integer with at least n palindromic representations of length >= 3 in bases b >= 2. %C A275220 a(9) and a(10) are identical because there is no number less than 35101 with nine palindromic representations in different bases; likewise for a(11) and a(12), and for a(13) and a(14). %o A275220 (PARI) isok(k, n) = sum(b=2, k-1, (d=digits(k,b)) && (#d >= 3) && (Vecrev(d) == d)) >= n; %o A275220 a(n) = my(j=1); while(! isok(j, n), j++); j; \\ _Michel Marcus_, Jul 28 2016 %Y A275220 Cf. A123586. %K A275220 base,nonn %O A275220 1,1 %A A275220 _Clive Stott_, Jul 20 2016 %E A275220 a(17)-a(32) from _Giovanni Resta_, Jul 28 2016