a(n) = (2^(n+4)-1)*(2^n+1).

Terms

a(0) =30a(1) =93a(2) =315a(3) =1143a(4) =4335a(5) =16863a(6) =66495a(7) =264063a(8) =1052415a(9) =4201983a(10) =16792575a(11) =67139583a(12) =268496895a(13) =1073864703a(14) =4295213055a(15) =17180360703a(16) =68720459775a(17) =274879873023