a(n) = A101254(n) + A098661(n).

Terms

a(0) =4a(1) =52a(2) =232a(3) =1028a(4) =3846a(5) =16678a(6) =89584a(7) =409894a(8) =2166630a(9) =12433014a(10) =67381452a(11) =468282278a(12) =2914549798a(13) =23237125624a(14) =148957518364