====== 小学数学题系列 ======

  * [[notes:math:xiaohong]]
  * [[notes:math:covenentfeeworthit]]
  * [[notes:math:power_of_2_last_digit]]
  * [[notes:math:triangle_15]]
  * [[notes:math:199_200vs200_199]]
  * [[notes:math:xx22048]]
  * [[notes:math:x6-1]]
  * [[notes:math:decreasing_number]]