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 A087152 #12 May 24 2017 21:18:59 %S A087152 1,3,20,194,2554,42226,843744,19769256,531768120,16152296424, %T A087152 546895099200,20425461026736,834215500905552,36988602430554576, %U A087152 1769524998544143360,90851799797294235264,4982968503277896871296 %N A087152 Expansion of (1-sqrt(1-4*log(1+x)))/log(1+x)/2. %H A087152 G. C. Greubel, <a href="/A087152/b087152.txt">Table of n, a(n) for n = 1..370</a> %F A087152 a(n) = Sum_{k=0..n} Stirling1(n, k)*k!*Catalan(k). %F A087152 a(n) ~ 2*n! / (exp(1/8)*sqrt(Pi) * (exp(1/4)-1)^(n-1/2) * n^(3/2)). - _Vaclav Kotesovec_, May 03 2015 %t A087152 Rest[CoefficientList[Series[(1-Sqrt[1-4*Log[1+x]])/Log[1+x]/2, {x, 0, 20}], x] * Range[0, 20]!] (* _Vaclav Kotesovec_, May 03 2015 *) %o A087152 (PARI) x='x+O('x^50); Vec(serlaplace((1-sqrt(1-4*log(1+x)))/log(1+x)/2 - 1)) \\ _G. C. Greubel_, May 24 2017 %Y A087152 Cf. A000108, A052851, A052803, A052886, A052895, A006531, A048287. %K A087152 nonn %O A087152 1,2 %A A087152 _Vladeta Jovovic_, Oct 18 2003