a(n) = n! * Sum_{k=0..n} A000296(k)/k!.

Terms

a(0) =1a(1) =1a(2) =3a(3) =10a(4) =44a(5) =231a(6) =1427a(7) =10151a(8) =81923a(9) =740732a(10) =7425042a(11) =81773715a(12) =981864897a(13) =12767876941a(14) =178774288331