(defun week-days (y m d)
  (let ((dow (nth 6 (decode-time (encode-time 0 0 0 d m y)))))
    (mapcar (lambda (x)
              (format-time-string "%Y/%m/%d(%a)"
                                  (encode-time 0 0 0 (- d dow (- x)) m y)))
            '(1 2 3 4 5))))