a(n) = floor(Fibonacci(n)/3).

Terms

a(0) =0a(1) =0a(2) =0a(3) =0a(4) =1a(5) =1a(6) =2a(7) =4a(8) =7a(9) =11a(10) =18a(11) =29a(12) =48a(13) =77a(14) =125a(15) =203a(16) =329a(17) =532a(18) =861a(19) =1393a(20) =2255a(21) =3648a(22) =5903a(23) =9552a(24) =15456a(25) =25008a(26) =40464a(27) =65472a(28) =105937a(29) =171409