a(n) = floor(n*phi^12), where phi is the golden ratio, A001622.

Terms

a(0) =0a(1) =321a(2) =643a(3) =965a(4) =1287a(5) =1609a(6) =1931a(7) =2253a(8) =2575a(9) =2897a(10) =3219a(11) =3541a(12) =3863a(13) =4185a(14) =4507a(15) =4829a(16) =5151a(17) =5473a(18) =5795a(19) =6117a(20) =6439a(21) =6761a(22) =7083a(23) =7405a(24) =7727a(25) =8049a(26) =8371a(27) =8693a(28) =9015a(29) =9337