Take two numbers arbitrarily from 3, 4, 5, 10, 12, 26 each time, one as the numerator and one as the denominator, many different fractions can be formed, how many of them are the simplest true fractions.
每次从3、4、5、10、12、26中任意取两个数，一个作分子，一个作分母，可以组成很多不同的分数，其中是最简真分数的有多少个．
<result>7</result>