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A135820
Finite sequence of moves needed to flip the top uf, ub edges in a 3 X 3 X 3 Rubik's Cube.
6
14, 14, 98, 56, 56, 392
OFFSET
1,1
COMMENTS
r,l,u,d,f,b are respectively right, left, up, down, front, back faces of a 3 X 3 X 3 Rubik's Cube. Set M=2, R=3, L=5, U=7, D=11, F=13, B=17, where M is a 90-degree turn of the middle slice of Rubik's Cube; R is a 90-degree turn of the right face, L is a 90-degree turn of the left face...
The moves to flip the top uf, ub edges are (M*U)*(M*U)*(M*U)*U*(M^3*U)*(M^3*U)*(M^3*U)*U = (2*7)*(2*7)*(2*7^2)*(2^3*7)*(2^3*7)*(2^3*7^2) = 14*14*98*56*56*392; note that as the order of a 90-degree turn T is 4, then T^2 = T^-2 and T^3 = T^-1. Moves adapted from 'Adventures in group theory'.
REFERENCES
D. Joyner, 'Adventures in Group Theory', John Hopkins Press.
EXAMPLE
For example, the number 14 = 2*7 encodes M*U moves.
CROSSREFS
Sequence in context: A214463 A006662 A247516 * A377190 A165835 A134913
KEYWORD
fini,full,nonn
AUTHOR
STATUS
approved