let count_divisors n =
  let c = ref 0 in
  let i = ref 1 in
  while !i * !i <= n do
    if n mod !i = 0 then begin
      c := !c + 1;
      if !i * !i <> n then c := !c + 1
    end;
    i := !i + 1
  done;
  !c

let first_triangle_with_divs target =
  let t = ref 0 in
  let n = ref 0 in
  let found = ref false in
  while not !found do
    n := !n + 1;
    t := !t + !n;
    if count_divisors !t > target then found := true
  done;
  !t

;;

first_triangle_with_divs 10