defmodule Main do
  def input, do: IO.read(:line) |> String.trim
  def ii, do: input() |> String.to_integer
  def li, do: input() |> String.split |> Enum.map(&String.to_integer/1)
  def yn(b), do: IO.puts(if b, do: "Yes", else: "No")

  def main do
    [n, m] = li()

    x = div(n * (n+1), 2)
    case x <= m do
      true -> "Yes"
      false -> "No"
    end
    |> IO.puts
  end
end