def page(number)
      cache = cache(number)
      unless cache.nil?
        return cache
      end

      if exist_runner?(number)
        return nil
      end

      search_page = @agent.get(@url)

      # レースデータ取得エラー
      if search_page.uri.path == '/record'
        raise(RaceError.new(@url))
      end

      form = search_page.forms[0]
      form.number = number
      result_page = @agent.submit(form)
      return mkcache(result_page, number)
    end
def page(number)
      cache = cache(number)
      unless cache.nil?
        return cache
      end

      if exist_runner?(number)
        return nil
      end

      search_page = @agent.get(@url)

      # レースデータ取得エラー
      if search_page.uri.path == '/record'
        raise(RaceError.new(@url))
      end

      form = search_page.forms[0]
      form.number = number
      result_page = @agent.submit(form)
      return mkcache(result_page, number)
    end
結果ページデータを取得

 @param [String] number ナンバー
 @return [Mechanize::Page|nil] 結果ページデータ