a(n) = round(1000*log_2(n)).

Terms

a(0) =0a(1) =1000a(2) =1585a(3) =2000a(4) =2322a(5) =2585a(6) =2807a(7) =3000a(8) =3170a(9) =3322a(10) =3459a(11) =3585a(12) =3700a(13) =3807a(14) =3907a(15) =4000a(16) =4087a(17) =4170a(18) =4248a(19) =4322a(20) =4392a(21) =4459a(22) =4524a(23) =4585a(24) =4644a(25) =4700a(26) =4755a(27) =4807a(28) =4858a(29) =4907