a(n) = floor(n*phi^5), where phi is the golden ratio, A001622.

Terms

a(0) =0a(1) =11a(2) =22a(3) =33a(4) =44a(5) =55a(6) =66a(7) =77a(8) =88a(9) =99a(10) =110a(11) =121a(12) =133a(13) =144a(14) =155a(15) =166a(16) =177a(17) =188a(18) =199a(19) =210a(20) =221a(21) =232a(22) =243a(23) =255a(24) =266a(25) =277a(26) =288a(27) =299a(28) =310a(29) =321