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 A138361 #8 Sep 14 2016 08:56:26
%S A138361 3,1,1,-1,2,-5,0,-3,0,6,-6,3,0,-2,1,-1,-1,4,4,-4,0,-3,1,4,0,-7,1,5,-5,
%T A138361 3,2,-6,8,-2,1,-3,0,1,3,-7,0,0,2,-2,-1,3,-2,6,-1,1,1,-5,1,1,-5,7,1,-5,
%U A138361 3,2,-8,1,5,3,-2,-3,2,-5,3,5,-4,2,-3,0,4,1,0,-1,-8,3,0,2,2,-6,3,3,-5,5,-3,-1,1,1,4,-8,8,-3,-2,-1,4,-3,2,0,-4,5,-4,-1,3
%N A138361 First differences of A068985.
%t A138361 b = RealDigits[N[1/E, 1000]]; b = First[b]; a = {}; Do[k = b[[n + 1]] - b[[n]]; AppendTo[a, k], {n, 1, 999}]; a (*Artur Jasinski*)
%t A138361 Differences[RealDigits[1/E,10,120][[1]]] (* _Harvey P. Dale_, Sep 14 2016 *)
%Y A138361 Cf. A068985, A095916, A095942, A138345.
%K A138361 sign
%O A138361 1,1
%A A138361 _Artur Jasinski_, Mar 16 2008