a(n) = Fibonacci(n) + (-1)^n.

Terms

a(0) =1a(1) =0a(2) =2a(3) =1a(4) =4a(5) =4a(6) =9a(7) =12a(8) =22a(9) =33a(10) =56a(11) =88a(12) =145a(13) =232a(14) =378a(15) =609a(16) =988a(17) =1596a(18) =2585a(19) =4180a(20) =6766a(21) =10945a(22) =17712a(23) =28656a(24) =46369a(25) =75024a(26) =121394a(27) =196417a(28) =317812a(29) =514228