传说在古时候,夏禹治水来到洛水。洛水中浮起一只大乌龟,乌龟背上有一个奇怪的图(如图1)。图上有许多圆点,这些圆点表示什么意思呢?大家都弄不明白。一个人好奇地数了一下龟甲上的圆点数,再用数字表示出来,发现这里有非常有趣的关系。 Legend in ancient times, Xia Yu water came to Los water. A big turtle floats in the water, and a weird figure on the turtle’s back (Figure 1). There are many dots on the map. What do these dots mean? Everyone can not understand. A curious number of dots on the tortoise shell, and then expressed by numbers and found that there is a very interesting relationship.