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 A048407 #7 Oct 10 2019 23:18:22
%S A048407 0,1,2,3,4,5,6,7,8,9,16,27,38,49,50,61,72,83,94,161,272,383,494,505,
%T A048407 616,727,838,949,1616,2727,3838,4949,5050,6161,7272,8383,9494,16161,
%U A048407 27272,38383,49494,50505,61616,72727,83838,94949,161616,272727,383838
%N A048407 Numbers whose consecutive digits differ by 5.
%t A048407 Join[Range[0,9],Select[Range[400000],Union[Abs[Differences[ IntegerDigits[ #]]]] == {5}&]] (* _Harvey P. Dale_, Sep 23 2013 *)
%Y A048407 Cf. A033075, A033088, A033081, A048406-A048410.
%K A048407 nonn,base
%O A048407 0,3
%A A048407 _Patrick De Geest_, Apr 15 1999