For n odd a(n) = a(n-2) + a(n-3), for n even a(n) = a(n-2) + a(n-5); with a(1) = 0, a(2) = 1.

Terms

a(0) =0a(1) =1a(2) =0a(3) =1a(4) =1a(5) =1a(6) =2a(7) =1a(8) =3a(9) =2a(10) =4a(11) =4a(12) =6a(13) =7a(14) =10a(15) =11a(16) =17a(17) =17a(18) =28a(19) =27a(20) =45a(21) =44a(22) =72a(23) =72a(24) =116a(25) =117a(26) =188a(27) =189a(28) =305a(29) =305