a(n) = n! * [x^n] exp(exp(x)*(x + (n/2 - 1)*x^2)).
A320254
a(n) = n! * [x^n] exp(exp(x)*(x + (n/2 - 1)*x^2)).
Terms
- a(0) =1a(1) =1a(2) =3a(3) =16a(4) =125a(5) =1291a(6) =16177a(7) =241207a(8) =4153193a(9) =81082225a(10) =1770989921a(11) =42763506919
External references
- oeis: A320254