负数概念引进后，整数集和有理数集就完整地形成了。
With the introduction of negative numbers ， the whole numbers and rational numbers became complete .
2004年李敏[5]提出下整和图的概念.令Q+表示正有理数集。
In 2004 , Li min [ 5 ] introduced the concept of lower integral sum graph .
有理数集