a(n) = floor( Gamma(n + 3/4)/Gamma(3/4) ).

Terms

a(0) =1a(1) =0a(2) =1a(3) =3a(4) =13a(5) =64a(6) =369a(7) =2495a(8) =19338a(9) =169214a(10) =1649843a(11) =17735822a(12) =208395915a(13) =2657047923a(14) =36534408953a(15) =538882532060