a(n) = floor(63/n).

Terms

a(0) =63a(1) =31a(2) =21a(3) =15a(4) =12a(5) =10a(6) =9a(7) =7a(8) =7a(9) =6a(10) =5a(11) =5a(12) =4a(13) =4a(14) =4a(15) =3a(16) =3a(17) =3a(18) =3a(19) =3a(20) =3a(21) =2a(22) =2a(23) =2a(24) =2a(25) =2a(26) =2a(27) =2a(28) =2a(29) =2