a(n) = A152392(n)/n for n>=1.

Terms

a(0) =1a(1) =2a(2) =6a(3) =24a(4) =116a(5) =642a(6) =3954a(7) =26528a(8) =191368a(9) =1468514a(10) =11899358a(11) =101177336a(12) =898486540a(13) =8299327770a(14) =79481787362a(15) =786962615104