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 A107274 #8 Feb 22 2021 13:28:02
%S A107274 101101,102501,111111,112511,121151,122551
%N A107274 Vertically symmetrical dates MMDDYY ("condensed American notation") considered as numbers, in increasing order.
%C A107274 2 and 5 are taken as mirror images (as on calculator displays). a(1)=101101 and a(3)=111111, share the property to present also two symmetrical halves. From now on, the next one is Nov 11th 11.
%Y A107274 Cf. A053701, A106605.
%K A107274 base,easy,fini,full,nonn
%O A107274 1,1
%A A107274 _Alexandre Wajnberg_, May 19 2005