a(n) = (-1)^n * A000045(n) + 1.

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