Expansion of e.g.f. 1/(1 - 2*x)^(x/2).

Terms

a(0) =1a(1) =0a(2) =2a(3) =6a(4) =44a(5) =360a(6) =3744a(7) =46200a(8) =662864a(9) =10838016a(10) =198943200a(11) =4050937440a(12) =90613710912