%I A073178
%S A073178 1,2,13,180,4266,153180,7725510,519629040,44880355800,4835536256880,
%T A073178 635221698211800,99872627051181600,18507444606249152400,
%U A073178 3990439472567239692000,990119486841576670378800
%N A073178 a(n) = n!^2 times coefficient of x^n in e^(x*(3-x)/2/(1-x))/(1-x)^(1/
               2).
%D A073178 R. P. Stanley, Enumerative Combinatorics, Cambridge, Vol. 2, 1999; see 
               Problem 5.65(b).
%F A073178 e^(x*(3-x)/2/(1-x))/(1-x)^(1/2) = Sum_{n>=0} a(n)*x^n/n!^2. - Vladeta 
               Jovovic (vladeta(AT)eunet.rs), Aug 01 2006
%o A073178 (PARI) a(n)=if(n<0,0,n!^2*polcoeff(exp(x*(3-x)/2/(1-x)+x*O(x^n))/sqrt(1-x+x*O(x^n)),
               n))
%Y A073178 Cf. A049088.
%Y A073178 Sequence in context: A006905 A119400 A137610 this_sequence A062156 A049512 
               A003507
%Y A073178 Adjacent sequences: A073175 A073176 A073177 this_sequence A073179 A073180 
               A073181
%K A073178 nonn
%O A073178 0,2
%A A073178 Michael Somos, Jul 19 2002