Expansion of 1/sqrt(1 - 4*x - 8*x^3).

Terms

a(0) =1a(1) =2a(2) =6a(3) =24a(4) =94a(5) =372a(6) =1508a(7) =6192a(8) =25638a(9) =106908a(10) =448356a(11) =1889040a(12) =7989676a(13) =33902504a(14) =144259944a(15) =615330784a(16) =2630199942a(17) =11263613484a(18) =48315367076a(19) =207556060816a(20) =892819376964