Expansion of e.g.f. exp(x^3)/(1-x).

Terms

a(0) =1a(1) =1a(2) =2a(3) =12a(4) =48a(5) =240a(6) =1800a(7) =12600a(8) =100800a(9) =967680a(10) =9676800a(11) =106444800a(12) =1297296000a(13) =16864848000a(14) =236107872000