[ 1/{n*sqrt(3)} ], where {x} := x - [ x ].

Terms

a(0) =1a(1) =2a(2) =5a(3) =1a(4) =1a(5) =2a(6) =8a(7) =1a(8) =1a(9) =3a(10) =19a(11) =1a(12) =1a(13) =4a(14) =1a(15) =1a(16) =2a(17) =5a(18) =1a(19) =1a(20) =2a(21) =9a(22) =1a(23) =1a(24) =3a(25) =30a(26) =1a(27) =2a(28) =4a(29) =1