a(n) = A025179(n-2) + A102839(n-4), for n >= 4, with a(0) = a(2) = 0 and a(1) = a(3) = 1.

Terms

a(0) =0a(1) =1a(2) =0a(3) =1a(4) =1a(5) =5a(6) =13a(7) =41a(8) =121a(9) =366a(10) =1100a(11) =3319a(12) =10015a(13) =30253a(14) =91433a(15) =276475a(16) =836291a(17) =2530321a(18) =7657317a(19) =23175867a(20) =70150875a(21) =212349687a(22) =642803631a(23) =1945819299a(24) =5890003539a(25) =17828324220a(26) =53961228258a(27) =163314594513a(28) =494238394601