Elixir GenServer use of timeout as 3rd element return from init()

timeout_example.ex

defmodule TimeoutExample do
 use GenServer
 def init(_args), do: {:ok, 0, 5_000}
 def handle_info(:timeout, state) do   
   IO.inspect(state)
   {:noreply, state+1, 5_000 + state*1000}
 end
end

iex> {:ok, p} = GenServer.start(TimeoutExample, [])
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