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 A109527 #3 Jul 01 2012 12:19:49 %S A109527 0,0,0,0,0,0,0,1,0,0,0,2,0,0,1,0,0,0,1,1,0,0,1,2,0,0,2,0,0,0,2,1,0,0, %T A109527 2,2,0,0,5,0,0,0,5,1,0,1,0,0,0,1,0,1,0,1,0,2,0,1,1,0,0,1,1,1,0,1,1,2, %U A109527 0,1,2,0,0,1,2,1,0,1,2,2,0,1,5,0,0,1,5,1,0,2,0,0,0,2,0,1,0,2,0,2,0,2,1,0,0 %N A109527 Prague bus clock sequence. %C A109527 See the sequence as a succession of quadruplets showing the time (in hours and minutes). The sequence starts at midnight (00:00) and ends at 22:51 showing all sound times seen in a lateral mirror (if the clock in the bus indicates 22:51 one will read 15:22 in a lateral window, which is a possible time of the day, thus the quadruplet 2251 belongs to the sequence; the quadruplet 0825 is not in the sequence as 08:25 produces 25:80 in the window). On such a digital clock the only digits which produce another "mirror" digit are 0 (->0), 1 (->1), 2 (->5), 5(->2) and 8(->8). "8" must be discarded in this sequence and "5" carefully used. %Y A109527 Cf. A028354, A109571. %K A109527 base,easy,fini,nonn %O A109527 0,12 %A A109527 _Eric Angelini_ and others, Aug 29 2005