a(n) = floor(10*log(n)).

Terms

a(0) =0a(1) =6a(2) =10a(3) =13a(4) =16a(5) =17a(6) =19a(7) =20a(8) =21a(9) =23a(10) =23a(11) =24a(12) =25a(13) =26a(14) =27a(15) =27a(16) =28a(17) =28a(18) =29a(19) =29a(20) =30a(21) =30a(22) =31a(23) =31a(24) =32a(25) =32a(26) =32a(27) =33a(28) =33a(29) =34