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 A248759 #11 Oct 15 2014 20:59:39
%S A248759 1,6,9,4,6,1,0,2,9,0,3,2,0,7,4,1,2,8,6,4,6,9,2,6,7,0,5,2,9,8,9,9,6,3,
%T A248759 3,3,1,6,9,7,1,2,4,2,9,9,3,7,7,4,0,8,0,0,4,2,0,5,5,4,0,2,5,1,0,0,6,3,
%U A248759 6,1,1,8,6,6,1,1,6,0,3,2,1,4,0,2,9,9
%N A248759 Decimal expansion of sum_{n>=1} n!/(3n)!.
%e A248759 0.1694610290320741286469267052989963331697124299377408004205540251006361...
%p A248759 evalf(sum(n!/(3*n)!, n=1..infinity),120) # _Vaclav Kotesovec_, Oct 15 2014
%t A248759 u = N[Sum[n!/(3 n)!, {n, 1, 200}], 120]
%t A248759 RealDigits[u] (* A248759 *)
%t A248759 N[HypergeometricPFQ[{1}, {4/3, 5/3}, 1/27]/6,120] (* _Vaclav Kotesovec_, Oct 15 2014 *)
%o A248759 (PARI) suminf(n=1, n!/(3*n)!) \\ _Michel Marcus_, Oct 15 2014
%Y A248759 Cf. A214869, A248696, A248760, A248761.
%K A248759 nonn,easy,cons
%O A248759 0,2
%A A248759 _Clark Kimberling_, Oct 13 2014