a(n) = A027082(n, 2n-10).

Terms

a(0) =1a(1) =1a(2) =5a(3) =17a(4) =57a(5) =193a(6) =653a(7) =2206a(8) =7431a(9) =24920a(10) =83099a(11) =275334a(12) =906103a(13) =2961539a(14) =9614823a(15) =31014965a(16) =99440907a(17) =317028068a(18) =1005424803a(19) =3173208229a(20) =9970459645a(21) =31200384655a(22) =97270715153a(23) =302217221275a(24) =936046187573