推了几个特别好记的MU流三棱换公式，原理是五循环叠加三循环，公式非常有规律，做几遍就能记住,虽然挺长但还是比较顺手
顺时针三棱换中间夹U'，逆时针夹U
正向
(M'U2M)U'(M'U2M)U'(M'U2M)
(M'U2M)U(M'U2M)U(M'U2M)
反向
(MU2M')U'(MU2M')U'(MU2M')
(MU2M')U(MU2M')U(MU2M')U'