local mod = 1000000007
local function badd(x, y) return (x + y) % mod end
local n = io.read("*n")
local t = {}
for i = 1, n do t[i] = 0 end
for i = n, 3, -1 do
  t[i] = 1
  for j = 1, n - i do
    t[j + i] = badd(t[j + i], t[j])
  end
end
print(t[n])

--[[
8
5 3
4 4
]]