Integer nearest n*sqrt(3).

Terms

a(0) =0a(1) =2a(2) =3a(3) =5a(4) =7a(5) =9a(6) =10a(7) =12a(8) =14a(9) =16a(10) =17a(11) =19a(12) =21a(13) =23a(14) =24a(15) =26a(16) =28a(17) =29a(18) =31a(19) =33a(20) =35a(21) =36a(22) =38a(23) =40a(24) =42a(25) =43a(26) =45a(27) =47a(28) =48a(29) =50