对称不等区集排列
symmetrical unequal block arrangement
多重集排列
permutation of multiple-sets
含小集的集族
the family of sets including small sets
易磁化轴平行排列的晶粒集团
grain group with easy axes parallel to each other
Smarandache7问题中逆序排列的偶数数列
the Smarandache back concatenated even sequences