a(n) = Sum_{k=0..n} A059432(n,k).

Terms

a(0) =1a(1) =1a(2) =3a(3) =15a(4) =116a(5) =1275a(6) =18909a(7) =363749a(8) =8807403a(9) =262089849a(10) =9401686696a(11) =400089347172