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 A321310 #25 Dec 01 2018 09:39:17
%S A321310 0,0,1,1,2,5,5,2,8,8,11,11,12,51,15,21,18,81,21,15,22,55,25,25,28,85,
%T A321310 51,12,52,52,55,22,58,82,81,18,82,58,85,28,88,88,101,101,102,501,105,
%U A321310 201,108,801,111,111,112,511,115,211,118,811,121,151,122,551
%N A321310 List of pairs of numbers with mirror symmetry (calculator-style numerals).
%C A321310 2 and 5 are taken as mirror images (as on calculator displays).
%e A321310 The sequence begins:
%e A321310 0, 0;
%e A321310 1, 1;
%e A321310 2, 5;
%e A321310 5, 2;
%e A321310 8, 8;
%e A321310 11, 11;
%e A321310 12, 51;
%e A321310 15, 21;
%e A321310 18, 81;
%e A321310 21, 15;
%e A321310 22, 55;
%e A321310 25, 25;
%e A321310 28, 85;
%e A321310 ...
%e A321310 81 has its reflection as 18 in a mirror.
%e A321310 125 has its reflection as 251 in a mirror.
%t A321310 {0, 0}~Join~Array[If[Mod[#, 10] == 0, Nothing, If[IntegerLength[#1] == Length[#2], {#1, FromDigits@ #2}, Nothing] & @@ {#, Reverse@ IntegerDigits@ # /. {2 -> 5, 3 -> Nothing, 4 -> Nothing, 5 -> 2, 6 -> Nothing, 7 -> Nothing, 9 -> Nothing}}] &, 123] // Flatten (* _Michael De Vlieger_, Nov 05 2018 *)
%Y A321310 Cf. A018846, A053701, A080228.
%K A321310 nonn,base,tabf
%O A321310 0,5
%A A321310 _Kritsada Moomuang_, Nov 03 2018