4-step Fibonacci sequence starting with 0, 1, 1, 0.

Terms

a(0) =0a(1) =1a(2) =1a(3) =0a(4) =2a(5) =4a(6) =7a(7) =13a(8) =26a(9) =50a(10) =96a(11) =185a(12) =357a(13) =688a(14) =1326a(15) =2556a(16) =4927a(17) =9497a(18) =18306a(19) =35286a(20) =68016a(21) =131105a(22) =252713a(23) =487120a(24) =938954a(25) =1809892a(26) =3488679a(27) =6724645a(28) =12962170a(29) =24985386