Expansion of Sum_{k>=0} k! * ( x/(1-x^3) )^k.

Terms

a(0) =1a(1) =1a(2) =2a(3) =6a(4) =25a(5) =124a(6) =738a(7) =5137a(8) =40926a(9) =367236a(10) =3664321a(11) =40241168a(12) =482282700a(13) =6263450401a(14) =87618831730