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 A117338 #3 Mar 30 2012 18:36:56
%S A117338 1,2,1,4,-9,62,-399,3048,-26045,247298,-2582027,29416876,-363327081,
%T A117338 4837734374,-69105690039,1054490587824,-17122237729589,
%U A117338 294828907099274,-5366869867749347,102988994579465716,-2078107926978317889,43988545301378533742
%N A117338 Row sums of triangle A117335.
%F A117338 G.f.: A(x) = 1/(1-x)/[Sum_{n>=0} (-1)^n*n!*x^n].
%e A117338 A(x) = 1 + 2*x + x^2 + 4*x^3 - 9*x^4 + 62*x^5 - 399*x^6 +-...
%e A117338 = 1/(1-x)/(1 - x + 2*x^2 - 6*x^3 + 24*x^4 - 120*x^5 +-...)
%o A117338 (PARI) a(n)=polcoeff(1/((1-x)*sum(k=0,n,(-1)^k*k!*x^k)+x*O(x^n)),n)
%Y A117338 Cf. A117335 (triangle), A117336 (column 1), A117337 (column 2).
%K A117338 sign
%O A117338 0,2
%A A117338 _Paul D. Hanna_, Mar 09 2006