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%I #14 Jan 30 2020 21:29:18
%S 0,1,4,22,116,600,3072,15634,79256,400718,2022160,10189974,51292608,
%T 257965512,1296483996,6512176890,32694946020,164082802440,
%U 823188507360,4128668625430,20701989426800,103781348220380,520167491584660,2606714240022090,13061050758478620,65434115386531850
%N Sum of the areas of all D-elevated skew paths of semi-length n.
%H Emeric Deutsch, Emanuele Munarini, Simone Rinaldi, <a href="http://dx.doi.org/10.1016/j.jspi.2009.12.013">Skew Dyck paths, area, and superdiagonal bargraphs</a>, Journal of Statistical Planning and Inference, Vol. 140, Issue 6, June 2010, pp. 1550-1562.
%F G.f.: x*(2-4*x-sqrt(1-6*x+5*x^2))/(1-5*x).
%F D-finite with recurrence: (-n+1)*a(n) +(11*n-20)*a(n-1) +5*(-7*n+19)*a(n-2) +25*(n-4)*a(n-3)=0.
%p g := x*(2-4*x-sqrt(1-6*x+5*x^2))/(1-5*x) ;
%p taylor(g,x=0,40) ;
%p gfun[seriestolist](%) ;
%K nonn,easy
%O 0,3
%A _R. J. Mathar_, Jun 21 2018