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 A138131 #12 Dec 03 2022 19:13:08
%S A138131 0,101,202,303,404,505,606,707,808,909,11011,12021,13031,14041,15051,
%T A138131 16061,17071,18081,19091,21012,22022,23032,24042,25052,26062,27072,
%U A138131 28082,29092,31013,32023,33033,34043,35053,36063,37073,38083
%N A138131 Palindromic cyclops numbers.
%C A138131 For prime entries in the sequence see A136098. - _Lekraj Beedassy_, Mar 15 2008, May 21 2008
%H A138131 Robert Israel, <a href="/A138131/b138131.txt">Table of n, a(n) for n = 1..10000</a>
%e A138131 101 is a member because 101 is a palindromic number A002113 and also a cyclops number A134808.
%p A138131 f:= proc(n,d) local L,m,k;
%p A138131 L:= convert(9^d+n,base,9);
%p A138131 add((1+L[d+1-i])*(10^(i-1)+10^(2*d+1-i)),i=1..d)
%p A138131 end proc:
%p A138131 seq(seq(f(n,d),n=0..9^d-1),d=0..2); # _Robert Israel_, Feb 18 2018
%t A138131 Join[{0},Flatten[Table[Select[Range[10^(2n),10^(2n+1)-1],PalindromeQ[ #] && DigitCount[ #,10,0]==1&&IntegerDigits[#][[(IntegerLength[#]+1)/2]]==0&],{n,2}]]] (* _Harvey P. Dale_, Dec 03 2022 *)
%Y A138131 Cf. A002113, A002385, A134808.
%K A138131 base,easy,nonn
%O A138131 1,2
%A A138131 _Omar E. Pol_, Mar 09 2008