let rec power ( * ) e m n =
  if n <= 0 then e
  else power ( * ) (if n land 1 = 0 then e else m * e) (m * m) (n lsr 1)

let m = 1000000007
let ( +^ ) x y = (x + y) mod m
let ( -^ ) x y = x +^ (m - y)
let ( *^ ) x y = (x * y) mod m

let perm n k =
  Array.fold_left ( *^ ) 1 @@
  Array.init k @@ ( + ) (n - k + 1)
let comb n k = power ( *^ ) (perm n k) (perm k k) (m - 2)
let hcomb n k = comb (n + k - 1) k

let () =
  let s = read_int () in
  Printf.printf "%d\n" @@
  Array.fold_left ( +^ ) 0 @@
  Array.init (s / 3) @@ fun n -> hcomb (n + 1) (s - 3 * (n + 1))