a(n) = F(n)*L(n-2) where F = Fibonacci and L = Lucas numbers.

Terms

a(0) =0a(1) =-1a(2) =2a(3) =2a(4) =9a(5) =20a(6) =56a(7) =143a(8) =378a(9) =986a(10) =2585a(11) =6764a(12) =17712a(13) =46367a(14) =121394a(15) =317810a(16) =832041a(17) =2178308a(18) =5702888a(19) =14930351a(20) =39088170a(21) =102334154a(22) =267914297a(23) =701408732a(24) =1836311904a(25) =4807526975a(26) =12586269026a(27) =32951280098a(28) =86267571273a(29) =225851433716