数码方幂和问题的两条性质及ｍ＝４，５时的循环圈设则对记则已知对任何为周期数列，数列｛ｎＫ｝的周期节称为循环圈．据［１］称，已找到ｍ＝１，２，３时的所有圈．我们通过计算机搜索，找到了：ｍ＝４时，共６个圈：｛１｝｛８２０８｝，｛９４７４｝，｛１６３４｝，... The two properties of the digital square sum problem and the loop circle at m=4,5 are known to the rule for any periodic sequence, and the sequence of {nK} is called a cyclic circle. According to [1], all circles with m=1, 2, and 3 have been found. We searched through the computer and found: When m=4, a total of 6 circles: {1}{8208}, {9474}, {1634},...