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 A190863 #10 Apr 25 2016 11:45:32
%S A190863 1,1,1,4,13,16,61,736,1849,-12032,15481,1386496,737221,-139053056,
%T A190863 8889973,22783492096,577232881,-4931048505344,9090479089,
%U A190863 1391155770032128,747609240061,-492982133885763584,14533568173741,214285634326006595584
%N A190863 E.g.f. exp(x*sqrt(1+x^2)).
%H A190863 Vincenzo Librandi, <a href="/A190863/b190863.txt">Table of n, a(n) for n = 0..105</a>
%F A190863 a(n)=n!*sum(k=1..n, (binomial(k/2,(n-k)/2)*((-1)^(n-k)+1))/k!)/2.
%t A190863 With[{nn=30},CoefficientList[Series[Exp[x Sqrt[1+x^2]],{x,0,nn}],x]Range[0,nn]!] (* _Harvey P. Dale_, Mar 23 2013 *)
%o A190863 (Maxima)
%o A190863 a(n):=n!*sum((binomial((k)/2,(n-k)/2)*((-1)^(n-k)+1))/k!,k,1,n)/2;
%o A190863 (PARI) x='x+O('x^66); /* that many terms */
%o A190863 Vec(serlaplace(exp(x*sqrt(1+x^2)))) /* show terms */ /* Joerg Arndt, May 22 2011 */
%K A190863 sign
%O A190863 0,4
%A A190863 _Vladimir Kruchinin_, May 21 2011