|
|
COMMENTS
| r,l,u,d,f,b are respectively right, left, up, down, front, back faces of a 3 X 3 Rubik's cube. Set M=2, R=3, L=5, U=7, D=11, F=13, B=17, where M is 90 degree turn of the middle slice of Rubik's cube; R is 90 degrees turn of the right face, L is 90 degree turn of the left face... The moves to permute (ufl,ubr)(ufr,ubl) corners are: (M^2*U)*(M^2*U^2)*(M^2*U)*(M^2*U^2)= (2^2*7)*(2^2*7^2)*(2^2*7)*(2^2*7^2)= 28*196*28*196 Note that as the order of 90 degrees turn T is 4, then T^2=T^-2 and T^3=T^-1. Moves adapted from 'Adventure in group theory', D. Joyner, J. Hopkins Press.
|
