let l () =
let p n=
let f m=
let rec _f s i m=
if i == 0 then s else _f (s + if m mod i == 0 then i else 0) (i - 1) m in _f 0 m m
in
Printf.printf "%d: %d\n" n (f n)
in
let rec r () =
p (int_of_string (read_line ()));
r ()
in
try r () with End_of_file -> ()
;;
l ()
Note that non-ascii characters in the above source code will be escaped (such as \x9f).