a(n) = floor(20/n).

Terms

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