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 A136592 #4 Feb 28 2013 09:27:57 %S A136592 1,3,-13,-10,394,-2016,-5076,170064,-1155024,-5005440,193724640, %T A136592 -1656720000,-10280355840,465087087360,-4804977542400,-39012996556800, %U A136592 2035558551398400,-24660231399014400,-248246498826547200,14713557956794368000 %N A136592 Column 2 of triangle A136590. %F A136592 E.g.f.: A(x) = log(1 + x + x^2)^2 / 2!. %e A136592 E.g.f.: A(x) = 1*x^2/2! + 3*x^3/3! - 13*x^4/4! - 10*x^5/5! + 394*x^6/6! +... %t A136592 With[{nn=30},Drop[CoefficientList[Series[Log[1+x+x^2]^2/2,{x,0,nn}],x] Range[ 0,nn]!,2]] (* _Harvey P. Dale_, Feb 28 2013 *) %o A136592 (PARI) a(n)=(n+2)!*polcoeff(log(1+x+x^2 +x*O(x^(n+2)))^2/2!,n+2) %Y A136592 Cf. A136590, A136591, A136593, A136594. %K A136592 sign %O A136592 2,2 %A A136592 _Paul D. Hanna_, Jan 10 2008