G.f. satisfies: AGM(1,A(x)) = 1 + 4*x.

Terms

a(0) =1a(1) =8a(2) =8a(3) =-16a(4) =48a(5) =-160a(6) =528a(7) =-1600a(8) =3952a(9) =-4512a(10) =-31040a(11) =322496a(12) =-2021584a(13) =10452384a(14) =-47768512a(15) =196396032a(16) =-719709808a(17) =2244001312a(18) =-5014625888a(19) =-511332480a(20) =96425281504a(21) =-773680460288