Floor(1/{(6+n^4)^(1/4)}), where {}=fractional part.

Terms

a(0) =1a(1) =6a(2) =18a(3) =43a(4) =83a(5) =144a(6) =228a(7) =341a(8) =486a(9) =666a(10) =887a(11) =1152a(12) =1464a(13) =1829a(14) =2250a(15) =2730a(16) =3275a(17) =3888a(18) =4572a(19) =5333a(20) =6174a(21) =7098a(22) =8111a(23) =9216a(24) =10416a(25) =11717a(26) =13122a(27) =14634a(28) =16259a(29) =18000