a(n) = Sum_{k >= 1} floor(n*phi^(2-k)).

Terms

a(0) =2a(1) =6a(2) =9a(3) =13a(4) =18a(5) =21a(6) =26a(7) =29a(8) =34a(9) =38a(10) =41a(11) =46a(12) =51a(13) =55a(14) =59a(15) =62a(16) =67a(17) =72a(18) =75a(19) =79a(20) =83a(21) =88a(22) =93a(23) =96a(24) =100a(25) =105a(26) =108a(27) =113a(28) =116a(29) =122